An antifreeze solution is prepared by dissolving $31\text{ g}$ of ethylene glycol (Molar mass = $62\text{ g mol}^{-1}$) in $600\text{ g}$ of water. Calculate the freezing point of the solution. ($K_f$ for water = $1\cdot86\text{ K kg mol}^{-1}$)
CBSE CLASS 12 • CHEMISTRY • CHAPTER 01
Solutions
276 distinct questions across 343 board paper set appearances (2022–2026).
Assertion (A) : When NaCl is added to water, a depression in freezing point is observed. Reason (R) : The lowering of vapour pressure of a solution causes depression in the freezing point.
Osmosis is a process by which the molecules of a solvent pass from a solution of low solute concentration to a solution of high solute concentration through a semi-permeable membrane. Osmotic pressure is a colligative property. When the applied pressure on a solution exceeds its osmotic pressure, re...
The mole fraction of a solute in $2\cdot 0$ molal aqueous solution is :
(A) $1\cdot 87$
(B) $0\cdot 347$
(C) $0\cdot 0347$
(D) $0\cdot 00347$
When a liquid and its vapour are at equilibrium and the pressure is suddenly decreased :
(A) vapour pressure of the solution increases
(B) heating occurs
(C) cooling occurs
(D) equilibrium remains unaffected
Answer the following questions :
(a) Why is direct current (DC) not used to measure the resistance of an ionic solution ?
(b) Why are the products of electrolysis different for the electrolysis of aqueous solution of $ ext{AgNO}_3$ with silver electrodes and electrolysis of aqueous solution of $ ext...
(a) $1\cdot00$ molal aqueous solution of trichloroacetic acid is heated to its boiling point. Boiling point of this solution was found to be $100\cdot18^{\circ}\text{C}$. Calculate the van't Hoff factor for trichloroacetic acid. (Given : $ ext{K}_\text{b}$ for water $= 0\cdot512 \text{ K kg mol}^{-1...
(c) The following reactions occur at the anode during the electrolysis of aqueous sodium chloride solution :
$\text{Cl}^- (\text{aq}) \longrightarrow \frac{1}{2} \text{Cl}_2 \, (g) + \text{e}^- \quad E^\circ_{(\text{cell})} = 1\cdot36 \text{ V} \quad (\text{I})$
$2\text{H}_2\text{O} \, (l) \longrigh...
(a) (i) Calculate the freezing point of a solution when $10\cdot5 \text{ g}$ of $\text{MgBr}_2$ was dissolved in $250 \text{ g}$ of water, assuming $\text{MgBr}_2$ undergoes complete dissociation.
(Given : Molar mass of $\text{MgBr}_2 = 184 \text{ g mol}^{-1}$,
$\text{K}_\text{f} \text{ for water} =...
According to the generally accepted definition of the ideal solution there are equal interaction forces acting between molecules belonging to the same or different species. (This is equivalent to the statement that the activity of the components equals the concentration.) Strictly speaking, this con...
While doing qualitative analysis in chemistry lab, Abhishek added yellow coloured potassium chromate solution into a test tube. He was surprised to see the colour of the solution changing immediately to orange. He realised that the test tube was not clean and contained a few drops of some liquid. Wh...
Assertion (A) : For measuring resistance of an ionic solution an AC source is used.
Reason (R) : Concentration of ionic solution will change if DC source is used.
(a) Calculate the elevation of boiling point of a solution when $3\text{ g}$ of $\text{CaCl}_2$ (Molar mass $= 111\text{ g mol}^{-1}$) was dissolved in $260\text{ g}$ of water, assuming that $\text{CaCl}_2$ undergoes complete dissociation. ($K_b$ for water $= 0\cdot52\text{ K kg mol}^{-1}$)
(a) Shweta mixed two liquids A and B of $10\text{ mL}$ each. After mixing, the volume of the solution was found to be $20\cdot2\text{ mL}$.
(i) Why was there a volume change after mixing the liquids ?
(ii) Will there be an increase or decrease of temperature after mixing ?
(iii) Give one example for...
(a) Write the name of the cell which is generally used in inverters. Write the reactions taking place at anode and cathode of this cell, when it is in use.
OR
(b) Explain why electrolysis of an aqueous solution of $ ext{NaCl}$ gives $ ext{H}_2$ gas at cathode and $ ext{Cl}_2$ gas at anode ? Write ov...
A compound $\text{CaCl}_2 \cdot 6\text{H}_2\text{O}$ undergoes complete dissociation in water. The Van't Hoff factor (i) is :
(A) 9
(B) 6
(C) 4
(D) 3
(a) Define Fuel cell. Write two advantages of fuel cell over ordinary cell.
OR
(b) Predict the products of electrolysis in each of the following :
(i) A dilute solution of $\text{H}_2\text{SO}_4$ with platinum electrodes
(ii) An aqueous solution of $\text{CuCl}_2$ with platinum electrodes
(a) (i) Define osmotic pressure. Why is it considered as a colligative property ?
(ii) The vapour pressure of two pure liquids A and B at $400\text{ K}$ are $450$ and $700\text{ mmHg}$ respectively. Find out the composition of liquid mixture if the total vapour pressure of mixture is $600\text{ mmHg...
An azeotropic mixture of two liquids has a boiling point higher than either of the two liquids when it : (a) shows large negative deviation from Raoult's law. (b) shows no deviation from Raoult's law. (c) shows large positive deviation from Raoult's law. (d) obeys Raoult's law.
(a) What type of deviation from Raoult's law is shown by a mixture of ethanol and acetone? Give reason. OR (b) Define Azeotrope. What type of azeotrope is formed by negative deviation from Raoult's law? Give an example.
(a) Illustrate Sandmeyer's reaction with an equation. (b) Explain, why $(\text{CH}_3)_2\text{NH}$ is more basic than $(\text{CH}_3)_3\text{N}$ in aqueous solution.
Raoult's law for volatile liquids states that the partial vapour pressure of each component in the solution is directly proportional to its mole fraction, whereas for a non-volatile solute, it states that the vapour pressure of a solution of a non-volatile solute is equal to the vapour pressure of t...
Arrange the following compounds as directed : (any Two)
(i) In decreasing order of basic strength in aqueous solution :
$\text{C}_2\text{H}_5\text{NH}_2, (\text{C}_2\text{H}_5)_2 \text{NH}, (\text{C}_2\text{H}_5)_3 \text{N}$
(ii) In increasing order of solubility in water :
$(\text{C}_2\text{H}_5)_2...
Calculate the boiling point of a solution containing $0.61\text{ g}$ of benzoic acid (Molar mass $= 122\text{ g mol}^{-1}$) in $5\text{ g}$ of $\text{CS}_2$ in which it dimerises to the extent of $88%$. The boiling point and $K_{\text{b}}$ of $\text{CS}_2$ are $46.2\text{ }^\circ\text{C}$ and $2.3\t...
Compound 'X' with molecular formula $\text{C}_4\text{H}_9\text{Br}$ reacts with aqueous $\text{KOH}$ to give an alcohol. The rate of this reaction depends only on the concentration of the compound 'X'. When an optically active isomer 'Y' of the compound 'X' was treated with aqueous $\text{KOH}$ solu...
On electrolysis of very dilute aqueous solution of $\text{NaCl}$ using platinum electrodes :
(A) $\text{H}_2$ gas is evolved at anode.
(B) $\text{Na}$ is produced at cathode.
(C) $\text{O}_2$ gas is evolved at anode.
(D) $\text{H}_2$ gas is evolved at cathode.
(a) (i) Describe giving reason which one of the following pairs has the property indicated :
(I) $\text{Fe}$ or $\text{Cu}$ – higher melting point
(II) $\text{Ti}^{3+}$ or $\text{Sc}^{3+}$ – coloured in aqueous solution
(III) $\text{Cr}$ or $\text{Zn}$ – higher third ionisation enthalpy
(ii) Write t...
(a) Explain the following with the help of Henry's law :
(i) Bends
(ii) Anoxia
OR
(b) How does sprinkling of salt help in clearing the snow covered roads in hilly areas ? Write the name of the colligative property involved in this process.
(a) Predict the products of electrolysis in each of the following :
(i) An aqueous solution of $\text{CuCl}_2$ with platinum electrodes.
(ii) A concentrated solution of $\text{H}_2\text{SO}_4$ with platinum electrodes.
Match Column I with Column II and choose the correct option :
Column I
Column II
a. Osmotic pressure
i. $\Delta T_{\text{f}} = K_{\text{f}}m$
b. Elevation of boiling point
ii. $\pi = CRT$
c. Depression of freezing point
iii. $\frac{P_1^0 - P_1}{P_1^0} = \frac{W_2 \times M_1}{M_2 \times W_1}$
d. Rela...
$10\text{ g}$ of a non-volatile solute is dissolved in $200\text{ g}$ of water to make a solution. It has a vapour pressure of $31\cdot84\text{ mm Hg}$ at $308\text{ K}$. Calculate the molar mass of the solute.
[Given : Vapour pressure of pure water at $308\text{ K} = 32\text{ mm Hg}$]
$2\text{ g}$ of $\text{Na}_2\text{SO}_4$ is dissolved in $50\text{ g}$ of water to form a solution. Calculate the freezing point of this solution, assuming $\text{Na}_2\text{SO}_4$ undergoes complete dissociation.
[Given : Molar mass of $\text{Na}_2\text{SO}_4 = 142\text{ g mol}^{-1}$, $\text{K}_\te...
$\text{PtCl}_4 \cdot 2\text{KCl}$ doesn't give precipitate of $\text{AgCl}$ with $\text{AgNO}_3$ solution. Write the structural formula and IUPAC name of the complex.
Assertion (A) : Henry's law constant ($K_{ ext{H}}$) decreases with increase in temperature.
Reason (R) : As the temperature increases, solubility of gases in liquids decreases.
(c) (i) Arrange the following complexes in the increasing order of conductivity of their solution :
$[\text{Cr}(\text{NH}_3)_3\text{Cl}_3]$, $[\text{Cr}(\text{NH}_3)_6]\text{Cl}_3$, $[\text{Cr}(\text{NH}_3)_5\text{Cl}]\text{Cl}_2$
Vapour pressure of pure water at $298\text{ K}$ is $24\cdot8\text{ mm Hg}$. Calculate the lowering in vapour pressure of an aqueous solution which freezes at $-0\cdot3^{\circ}\text{C}$. ($K_f$ of water $= 1\cdot86\text{ K kg mol}^{-1}$)
A 1% solution of solute 'X' is isotonic with a 6% solution of sucrose (molar mass = $342 \text{ g mol}^{-1}$). The molar mass of solute 'X' is :
(A) $34\cdot2 \text{ g mol}^{-1}$
(B) $57 \text{ g mol}^{-1}$
(C) $114 \text{ g mol}^{-1}$
(D) $3\cdot42 \text{ g mol}^{-1}$
Calculate elevation of the boiling point of the solution when $4 \text{ g}$ of $\text{MgSO}_4$ (molar mass = $120 \text{ g/mol}$) was dissolved in $100 \text{ g}$ of water, assuming $\text{MgSO}_4$ undergoes complete ionisation. ($K_b$ for water = $0.52 \text{ K kg mol}^{-1}$)
Assertion (A) : Conductivity decreases with decrease in concentration of electrolyte.
Reason (R) : Number of ions per unit volume that carry the current in a solution decreases on dilution.
The colligative property used for the determination of molar mass of polymers and proteins is : (a) Osmotic pressure (b) Depression in freezing point (c) Relative lowering in vapour pressure (d) Elevation is boiling point
What is Henry's law ? Give one application of it.
(a) (i) Carry out the following conversions:
(1) Ethanal to But-2-en-1-al
(2) Propanoic acid to 2-chloropropanoic acid
(ii) An alkene with molecular formula C$_5$H$_{10}$ on ozonolysis gives a mixture of two compounds 'B' and 'C'. Compound 'B' gives positive Fehling test and also reacts with iodine ...
OR (b) (i) Why is the value of Van't Hoff factor for ethanoic acid in benzene close to 0.5 ? (ii) Determine the osmotic pressure of a solution prepared by dissolving $2.32 \times 10^{-2}\text{g}$ of $\text{K}_2\text{SO}_4$ in 2L of solution at 25 °C, assuming that $\text{K}_2\text{SO}_4$ is complete...
(c) The vapour pressure of a solution of glucose in water is $750$ mm Hg at $100^{\circ}\text{C}$. Calculate the mole fraction of solute. (Vapour pressure of water at $373\text{ K} = 760\text{ mm Hg}$)
(a) Differentiate between the following :
(i) Adsorption and Absorption
(ii) Lyophobic Sol and Lyophilic Sol
(iii) Multimolecular Colloid and Macromolecular colloid.
OR
(b) (I) Define the following terms :
(i) Zeta Potential
(ii) Coagulation
(II) Why a negatively charged sol is obtained when $ ext{A...
(d) (i) What will happen to the concentration of $\text{Zn}^{2+}$ and $\text{Ag}^{+}$ when $E_{\text{cell}} = 0$.
(ii) Why does conductivity of a solution decreases with dilution?
What will happen during the electrolysis of aqueous solution of $\text{CuCl}_2$ by using platinum electrodes ?
(A) $\text{Cu}$ will deposit at Anode
(B) $\text{H}_2$ gas will be released at cathode
(C) $\text{O}_2$ gas will be released at anode
(D) $\text{Cl}_2$ gas will be released at anode
Assertion (A) : It is not possible to separate the components of an azeotrope by fractional distillation.
Reason (R) : Components of an azeotrope have the same composition in liquid and vapour phase and boil at a constant temperature.
Which of the following solutions will have the highest osmotic pressure ?
(A) $0.1 ext{ M KCl}$
(B) $0.1 ext{ M CaCl}_2$
(C) $0.1 ext{ M Glucose}$
(D) $0.1 ext{ M Urea}$
Assertion (A) : Components of azeotropes are easily separated by fractional distillation.
Reason (R) : Components of an azeotrope have same composition in liquid and vapour phase.
What type of deviation from Raoult's law is shown by mixture of ethanol and acetone ? Give reason. What will happen to the boiling point of the solution on mixing ethanol and acetone ?
Compound 'X' with molecular formula $ ext{C}_4 ext{H}_9 ext{Br}$ reacts with aqueous $ ext{KOH}$ to give an alcohol. The rate of this reaction depends only on the concentration of the compound 'X'. When an optically active isomer 'Y' of the compound 'X' was treated with aqueous $ ext{KOH}$ solution,...
Calculate the boiling point of a solution containing \(0.61 \text{ g}\) of benzoic acid \((\text{Molar mass} = 122 \text{ g mol}^{-1})\) in \(5 \text{ g}\) of \(\text{CS}_2\) in which it dimerises to the extent of \(88%\). The boiling point and \(\text{K}_\text{b}\) of \(\text{CS}_2\) are \(46.2 \te...
Which of the following is the correct expression of $\text{K}_\text{f}$ which depends upon the nature of solvent ?
(A) $\text{K}_\text{f} = \frac{\text{M}_1 \times \text{T}_\text{f}^2}{\text{R} \times 1000 \times \Delta_\text{fus}\text{H}}$
(B) $\text{K}_\text{f} = \frac{\text{R} \times \text{M}_1 \...
Assertion (A) : It is not possible to separate the components of an azeotrope by fractional distillation.
Reason (R) : Minimum boiling azeotrope is formed by the solutions showing large positive deviation from Raoult's law.
What type of deviation is shown by a mixture of chloroform and acetone from Raoult's law ? Give reason. What will happen to the boiling point of the solution on mixing chloroform and acetone ?
When $1.5\text{ g}$ of a non-volatile solute was dissolved in $90\text{ g}$ of benzene, the boiling point of benzene got raised from $353.23\text{ K}$ to $353.93\text{ K}$. Calculate the molar mass of the solute. (Given $\text{K}_\text{b}$ for benzene $= 2.52\text{ K kg mol}^{-1}$)
A solution containing $8.0 \text{ g}$ of a non-volatile solute in $100 \text{ g}$ of diethyl ether boils at $36.86^{\circ}\text{C}$ whereas pure diethyl ether boils at $35.60^{\circ}\text{C}$. Determine the molar mass of the solute.
$(K_{\text{b}} \text{ for diethyl ether } = 2.02 \text{ K kg mol}^{...
(b) Why osmotic pressure is more advantageous than other colligative properties ?
The value of Henry's law constant ($K_{\text{H}}$) _______
(A) increases with an increase in temperature
(B) remains constant with an increase in temperature
(C) decreases with an increase in temperature
(D) first increases, then decreases with an increase in temperature
An unripe mango placed in a concentrated saline solution to prepare pickles shrivels, because :
(A) it gains water due to osmosis.
(B) it loses water due to osmosis.
(C) it gains water due to reverse osmosis.
(D) it loses water due to reverse osmosis.
(a) Define osmotic pressure. Out of $1\text{ M KCl}$ and $1\text{ M}$ glucose solutions, which will have a higher osmotic pressure ? Justify your answer.
OR
(b) Give reasons for the following :
(i) An azeotrope distills without any change in composition.
(ii) Aquatic animals are more comfortable in ...
The freezing point of a solution containing $5\text{ g}$ of benzoic acid $(\text{Molar mass} = 122\text{ g mol}^{-1})$ in $35\text{ g}$ of benzene is depressed by $2\cdot94\text{ K}$. Calculate the percentage association of benzoic acid, if it forms a dimer in solution. ($K_f$ for benzene $= 4\cdot9...
Which of the following colligative properties can preferably determine the molar mass of proteins ?
(A) Relative lowering of vapour pressure
(B) Osmotic pressure
(C) Elevation of boiling point
(D) Depression of freezing point
For an electrolyte consisting of a monovalent cation and a monovalent anion undergoing dissociation in water, the van't Hoff factor (i) is :
(A) less than 1
(B) equal to 1
(C) greater than 1
(D) greater than 2
State Raoult's law for a solution containing volatile components. Write any two characteristics of a solution which obeys Raoult's law at all concentrations.
Calculate the molarity and molality of a $ ext{KI}$ solution if the density of $20%$ (mass/mass) aqueous solution of $ ext{KI}$ is $1\cdot 2 ext{ g mL}^{-1}$.
[Given : Molar mass of $ ext{KI} = 166 ext{ g mol}^{-1}$]
In aqueous solution, $ ext{Cr}_2 ext{O}_7^{2-}$ ion converts to which of the following in alkaline medium ?
(A) $ ext{Cr}^{3+}$
(B) $ ext{CrO}_4^{2-}$
(C) $ ext{CrO}$
(D) $ ext{CrO}_3$
The boiling point of an azeotropic mixture of water and ethanol is less than that of pure water and ethanol. The mixture shows :
(A) positive deviation from Raoult's Law.
(B) negative deviation from Raoult's Law.
(C) no deviation from Raoult's Law.
(D) that the solution is an ideal solution.
An antifreeze solution is prepared by dissolving $31 ext{ g}$ of ethylene glycol $( ext{Molar mass} = 62 ext{ g mol}^{-1})$ in $600 ext{ g}$ of water. Calculate the freezing point of the solution. ($K_{ ext{f}}$ for water $= 1 \cdot 86 ext{ K kg mol}^{-1}$)
(a) (i) Describe giving reason which one of the following pairs has the property indicated :
(I) $ ext{Fe}$ or $ ext{Cu}$ – higher melting point
(II) $ ext{Ti}^{3+}$ or $ ext{Sc}^{3+}$ – coloured in aqueous solution
(III) $ ext{Cr}$ or $ ext{Zn}$ – higher third ionisation enthalpy
(ii) Write the ion...
In aqueous acidified solution, $ ext{CrO}_4^{2-}$ ion converts to which of the following ?
(A) $ ext{CrO}_3$
(B) $ ext{Cr}^{3+}$
(C) $ ext{Cr}_2 ext{O}_7^{2-}$
(D) $ ext{CrO}$
The boiling point of an azeotropic mixture of water and nitric acid is more than that of pure water and nitric acid. The mixture shows :
(A) no deviation from Raoult's law
(B) that solution is an ideal solution
(C) positive deviation from Raoult's law
(D) negative deviation from Raoult's law
(b) (i) A black-brown coloured solid (A) when fused with $ ext{KOH}$ in the presence of air, produces a dark green coloured compound (B) which on electrolytic oxidation in alkaline medium gives a dark purple coloured compound (C). Identify (A), (B) and (C). Write the reactions involved.
(ii) What ha...
On electrolysis of very dilute aqueous solution of $ ext{NaCl}$ using platinum electrodes :
(A) $ ext{H}_2$ gas is evolved at anode.
(B) $ ext{Na}$ is produced at cathode.
(C) $ ext{O}_2$ gas is evolved at anode.
(D) $ ext{H}_2$ gas is evolved at cathode.
The correct order of decreasing basic strength in aqueous solution of the following is :
(A) $( ext{C}_2 ext{H}_5)_3 ext{N} > ext{C}_2 ext{H}_5 ext{NH}_2 > ( ext{C}_2 ext{H}_5)_2 ext{NH}$
(B) $( ext{C}_2 ext{H}_5)_2 ext{NH} > ext{C}_2 ext{H}_5 ext{NH}_2 > ( ext{C}_2 ext{H}_5)_3 ext{N}$
(C) $ ext{C...
$1$ mole of liquid A and $2$ moles of liquid B make a solution having a total vapour pressure $40$ torr. The vapour pressure of pure A and pure B are $30$ torr and $45$ torr respectively. The above solution :
(A) is an ideal solution.
(B) shows negative deviation from Raoult's Law.
(C) shows positiv...
An antifreeze solution is prepared by dissolving $31\text{ g}$ of ethylene glycol ($ ext{Molar mass} = 62\text{ g mol}^{-1}$) in $600\text{ g}$ of water. Calculate the freezing point of the solution. ($K_{\text{f}}$ for water $= 1\cdot86\text{ K kg mol}^{-1}$)
(a) (i) Calculate the electrode potential of a half-cell for zinc electrode dipping in $0.01\text{ M }\text{ZnSO}_4$ solution at $25^\circ\text{C}$.
Given : $E^\circ_{\text{Zn}^{2+}/\text{Zn}} = - 0.76\text{ V}$
$[\log 10 = 1]$
The correct order of decreasing basicities of $\text{C}_2\text{H}_5\text{NH}_2$, $(\text{C}_2\text{H}_5)_2\text{NH}$ and $(\text{C}_2\text{H}_5)_3\text{N}$ in aqueous solution is :
(A) $(\text{C}_2\text{H}_5)_3\text{N} > (\text{C}_2\text{H}_5)_2\text{NH} > \text{C}_2\text{H}_5\text{NH}_2$
(B) $(\tex...
The boiling point of one molal $\text{NaCl}$ solution, assuming $\text{NaCl}$ to be completely dissociated in water is : ($K_\text{b}$ for water = $0\cdot52\text{ K kg mol}^{-1}$)
(A) $100\cdot52^{\circ}\text{C}$
(B) $101\cdot04^{\circ}\text{C}$
(C) $100\cdot04^{\circ}\text{C}$
(D) $101\cdot52^{\cir...
The correct order of decreasing basic strength of $ ext{CH}_3 - ext{NH}_2$, $( ext{CH}_3)_2 ext{NH}$ and $( ext{CH}_3)_3 ext{N}$ in aqueous solution is :
(A) $( ext{CH}_3)_3 ext{N} > ( ext{CH}_3)_2 ext{NH} > ext{CH}_3 - ext{NH}_2$
(B) $ ext{CH}_3 - ext{NH}_2 > ( ext{CH}_3)_2 ext{NH} > ( ext{CH}_...
The boiling point of one molal $ ext{NaCl}$ solution, assuming $ ext{NaCl}$ to be completely dissociated in water is : ($K_{ ext{b}}$ for water $= 0.52 ext{ K kg mol}^{-1}$)
(A) $100.52^\circ ext{C}$
(B) $101.04^\circ ext{C}$
(C) $100.04^\circ ext{C}$
(D) $101.52^\circ ext{C}$
Which of the following is \textit{not} correct for $\text{S}_\text{N}1$ reaction ?
(A) Follows first order kinetics
(B) Favoured by polar protic solvents
(C) Proceeds through the formation of carbocation
(D) Results in inversion of configuration
The boiling point of one molal $\text{NaCl}$ solution, assuming $\text{NaCl}$ to be completely dissociated in water is : ($K_b$ for water $= 0\cdot52 \text{ K kg mol}^{-1}$)
(A) $100\cdot52^{\circ}\text{C}$
(B) $101\cdot04^{\circ}\text{C}$
(C) $100\cdot04^{\circ}\text{C}$
(D) $101\cdot52^{\circ}\tex...
(a) Explain the following with the help of Henry's law :
(i) Bends
(ii) Anoxia
OR
(b) How does sprinkling of salt help in clearing the snow covered roads in hilly areas ? Write the name of the colligative property involved in this process.
(b) State Henry's law. Calculate the mole fraction of $ ext{CO}_2$ in water at $298 ext{ K}$ under $760 ext{ mm Hg}$.
(Given : $K_H$ for $ ext{CO}_2$ in $ ext{H}_2 ext{O}$ at $298 ext{ K} = 1.25 imes 10^6 ext{ mm Hg}$)
(a) (ii) Write two differences between ideal and non-ideal solutions.
(b) (i) A solution is prepared by dissolving $0\cdot025 \text{ g}$ of potassium sulphate in $2 \text{ L}$ of water at $27^{\circ}\text{C}$. Assuming potassium sulphate is completely dissociated, determine its osmotic pressure.
(Given : $\text{R} = 0\cdot082 \text{ L atm K}^{-1} \text{ mol}^{-1}$,
Mo...
(b) (ii) What type of azeotrope will be formed by a solution of acetone and chloroform ? Give reason.
Answer the following questions :
(a) Predict the products of electrolysis in each of the following :
(i) An aqueous solution of $ ext{CuCl}_2$ with platinum electrodes.
(ii) A concentrated solution of $ ext{H}_2 ext{SO}_4$ with platinum electrodes.
(a) Name the cell used in hearing aids and watches.
(b) Define conductivity. Why is direct current (DC) not used for the measurement of resistance of an ionic solution ?
Assertion (A) : The volume of an ideal solution is equal to the sum of the volumes of the two components, i.e., $\Delta_{\text{mix}} \text{ V} = 0$.
Reason (R) : The intermolecular forces of attraction between the solute-solvent molecules are weaker than those between the solute-solute and solvent-s...
$2\text{ g}$ of $ ext{Na}_2 ext{SO}_4$ is dissolved in $50\text{ g}$ of water to form a solution. Calculate the freezing point of this solution, assuming $ ext{Na}_2 ext{SO}_4$ undergoes complete dissociation.
[Given : Molar mass of $ ext{Na}_2 ext{SO}_4 = 142\text{ g mol}^{-1}$,
$K_f \text{ for wat...
(ii) A solution of $[ ext{Ni}( ext{H}_2 ext{O})_6]^{2+}$ is green in colour while a solution of $[ ext{Ni}( ext{CN})_4]^{2-}$ is colourless. Explain.
[Atomic number : $ ext{Ni} = 28$]
OR
(b) (i) (I) Write IUPAC name of the given complexes :
$[ ext{Ag}( ext{CN})_2]\ [ ext{Ag}( ext{NH}_3)_2]$
(II) Wha...
Assertion (A) : The volume of an ideal solution is equal to the sum of the volumes of the two components, i.e., $\Delta_{\text{mix}} V = 0$.
Reason (R) : The intermolecular forces of attraction between the solute-solvent molecules are weaker than those between the solute-solute and solvent-solvent m...
$10\text{ g}$ of a non-volatile solute is dissolved in $200\text{ g}$ of water to make a solution. It has a vapour pressure of $31.84\text{ mm Hg}$ at $308\text{ K}$. Calculate the molar mass of the solute. [Given : Vapour pressure of pure water at $308\text{ K} = 32\text{ mm Hg}$]
Match Column I with Column II and choose the correct option :
Column I
a. Osmotic pressure
b. Elevation of boiling point
c. Depression of freezing point
d. Relative lowering of vapour pressure
Column II
i. $\Delta T_f = K_f m$
ii. $\pi = CRT$
iii. $\frac{P_1^0 - P_1}{P_1^0} = \frac{W_2 \times M_1}...
Assertion (A) : The volume of an ideal solution is equal to the sum of the volumes of the two components, i.e., $\Delta_{ ext{mix}} V = 0$.
Reason (R) : The intermolecular forces of attraction between the solute-solvent molecules are weaker than those between the solute-solute and solvent-solvent mo...
$70 ext{ gm}$ solute is dissolved in $700 ext{ gm}$ solvent to prepare a solution having density $1.5 ext{ g/ml}$. The ratio of its molality and molarity will be:
A. $0.77$
B. $1.4$
C. $0.73$
D. $1.3$
Assertion (A): Care should always be taken to ensure that solutions that flow in the blood stream are of the same osmotic pressure as that of the blood.
Reason(R): Sodium ion and potassium ions are responsible for maintaining proper osmotic pressure balance inside and outside of the cells of organis...
Attempt either option A or B\n\nA. Answer the following:\nI. When 50 $ ext{mL}$ of phenol and 50 $ ext{mL}$ of aniline are mixed, predict whether the volume of the solution is equal to, greater than or less than 100 $ ext{mL}$. Give reason to support your answer.\nII. Ritesh suggested adding salt to...
What will be the vapour pressure of a 1 molal aqueous solution of $ ext{MgCl}_2$, assuming dissociation of $ ext{MgCl}_2$ to be 70 mole percent? (Vapor pressure of pure water at $25 ext{ }^\circ ext{C}$ is $23.8 ext{ mmHg}$)
Conductivity of Aqueous Solutions
Electrical conductivity is based on the flow of ions. Slightly ionized substances are weak electrolytes. Weak acids and bases would be categorized as weak electrolytes because they do not completely dissociate in solution.
Highly ionized substances are strong elec...
Based on the information provided above, answer the following questions:
I. Is it possible to identify whether the given solution is $1\text{ M NaOH}$ or $1\text{ M HCl}$ using the conductivity meter? Justify your answer.
II. What is the possible pH value of solution if the glow of green LED is me...
Based on the information provided above, answer the following questions:
| Scale | Conductivity |
| --- | --- |
| 0 | low or none |
| 1 | low |
| 2 | medium |
| 3 | high |
| 4 | very high |
I. Is it possible to identify whether the given solution is $1\text{ M NaOH}$ or $1\text{ M HCl}$ using th...
The colligative property preferred for the determination of molar mass of polymers is :
(A) Depression in freezing point
(B) Osmotic pressure
(C) Relative lowering in vapour pressure
(D) Elevation in boiling point
Define azeotropes. What type of azeotrope is formed by negative deviation from Raoult's law ?
A solution is prepared by dissolving $5\text{ g}$ of non-volatile solute in $100\text{ g}$ of water. It has a vapour pressure of $31\cdot84\text{ mm Hg}$ at $306\text{ K}$. Calculate the molar mass of the solute.\n[Vapour pressure of pure water = $32\text{ mm Hg}$]
An azeotropic mixture of two liquids has a boiling point higher than that of either of the two liquids when it
(A) obeys Raoult's law.
(B) shows positive deviation from Raoult's law.
(C) shows negative deviation from Raoult's law.
(D) obeys Henry's law.
Solubility of gases in liquid decreases with increase in
(A) pressure
(B) volume
(C) number of solute particles
(D) temperature
(A) (a) Account for the following :
(i) Transition metals and their compounds show catalytic activities.
(ii) $ ext{Mn}^{3+}$ is a strong oxidising agent.
(iii) $ ext{Cu}^{+}$ is not stable in aqueous solution.
(b) Write the preparation of $ ext{KMnO}_4$ from Pyrolusite ore ($ ext{MnO}_2$).
33. (A) (a) Calculate the boiling point of solution when $6\text{ g}$ of $\text{MgSO}_4$ (Molar mass $= 120\text{ g mol}^{-1}$) was dissolved in $200\text{ g}$ of water, assuming the complete dissociation of $\text{MgSO}_4$. ($K_{\text{b}}$ for water $= 0.52\text{ K kg mol}^{-1}$).
(b) State Raoult...
Out of $\text{Fe}^{3+}$, $\text{Sc}^{3+}$, $\text{Cr}^{3+}$ and $\text{Co}^{3+}$ ions, the one which is colourless in aqueous solution is :
(A) $\text{Sc}^{3+}$
(B) $\text{Fe}^{3+}$
(C) $\text{Cr}^{3+}$
(D) $\text{Co}^{3+}$
[Atomic number : $\text{Fe} = 26$, $\text{Sc} = 21$, $\text{Cr} = 24$, $\tex...
An aqueous solution of $\text{NaOH}$ was made and its molar mass from the measurement of osmotic pressure at $27\,^\circ\text{C}$ was found to be $25\text{ g mol}^{-1}$. Calculate the percentage dissociation of $\text{NaOH}$ in this solution. $[Atomic mass : \text{Na} = 23\text{ u}, \text{O} = 16\te...
OR
(b) (i) The rate of the chemical reaction doubles for an increase of $10\text{ K}$ in absolute temperature from $298\text{ K}$. Calculate activation energy ($E_a$).
$[2\cdot303\text{ R} = 19\cdot15\text{ J K}^{-1}\text{ mol}^{-1},\text{ log } 2 = 0\cdot3]$
An aqueous solution of $\text{NaOH}$ was made and its molar mass from the measurement of osmotic pressure at $27^{\circ}\text{C}$ was found to be $25 \text{ g mol}^{-1}$. Calculate the percentage dissociation of $\text{NaOH}$ in this solution.
[Atomic mass : $\text{Na} = 23 \text{ u}$, $\text{O} = 1...
Out of $\text{Ti}^{3+}$, $\text{Cr}^{3+}$, $\text{Fe}^{2+}$ and $\text{Ni}^{2+}$ ions, the one which is the most stable ion in aqueous solution is :
(A) $\text{Ti}^{3+}$
(B) $\text{Cr}^{3+}$
(C) $\text{Fe}^{2+}$
(D) $\text{Ni}^{2+}$
[Atomic number : $\text{Ti} = 22$, $\text{Cr} = 24$, $\text{Fe} = 2...
$\text{PdCl}_2 \cdot 2\text{KCl}$ does not give precipitate of $\text{AgCl}$ with $\text{AgNO}_3$ solution. Write the structural formula and IUPAC name of the complex.
An aqueous solution of $\text{NaOH}$ was made and its molar mass from the measurement of osmotic pressure at $25^\circ\text{C}$ was found to be $28 \text{ g mol}^{-1}$. Calculate the percentage dissociation of $\text{NaOH}$ in this solution.
[Atomic mass : $\text{Na} = 23\cdot0 \text{ u}, \text{O} =...
(b) (i) The rate of the chemical reaction doubles for an increase of $10\text{ K}$ in absolute temperature from $298\text{ K}$. Calculate activation energy ($E_a$).
$[2\cdot 303\text{ R} = 19\cdot 15\text{ J K}^{-1}\text{ mol}^{-1},\ \log 2 = 0\cdot 3]$
In which of the following groups are both ions coloured in aqueous solution ?
I. $\text{Cu}^+$ $\quad$ II. $\text{Ti}^{4+}$ $\quad$ III. $\text{Co}^{2+}$ $\quad$ IV. $\text{Fe}^{2+}$
[Atomic number : $\text{Cu} = 29$, $\text{Ti} = 22$, $\text{Co} = 27$, $\text{Fe} = 26$]
(A) I and II $\quad$ (B) II ...
OR
(b) Liquids 'X' and 'Y' form an ideal solution. The vapour pressure of pure 'X' and pure 'Y' are $120\text{ mm Hg}$ and $160\text{ mm Hg}$ respectively. Calculate the vapour pressure of the solution containing equal moles of 'X' and 'Y'.
(b) (ii) $\Lambda^\circ_{\text{m}} \text{NH}_4\text{Cl}$, $\Lambda^\circ_{\text{m}} \text{NaOH}$ and $\Lambda^\circ_{\text{m}} \text{NaCl}$ are $129\cdot8$, $217\cdot4$, and $108\cdot9\text{ S cm}^2\text{ mol}^{-1}$ respectively. Molar conductivity of $1 \times 10^{-2}\text{ M}$ solution of $\text{N...
In which of the following groups are both ions coloured in aqueous solution ?
$\text{I. Cu}^+\quad\quad\quad\text{II. Ti}^{4+}\quad\quad\quad\text{III. Co}^{2+}\quad\quad\quad\text{IV. Fe}^{2+}$
[Atomic number : $\text{Cu} = 29$, $\text{Ti} = 22$, $\text{Co} = 27$, $\text{Fe} = 26$]
(A) \text{I and ...
OR
(b) (i) How does sprinkling of salt help in clearing the snow covered roads in hilly areas ?
(ii) What happens when red blood cells are kept in $0\cdot5% \text{ (mass/vol)}$ $\text{NaCl}$ solution ? Justify your answer.
(iii) Write an application of reverse osmosis.
Arrange the following complexes in the increasing order of conductivity of their solution :
$[ ext{Cr}( ext{NH}_3)_3 ext{Cl}_3]$, $[ ext{Cr}( ext{NH}_3)_6] ext{Cl}_3$, $[ ext{Cr}( ext{NH}_3)_5 ext{Cl}] ext{Cl}_2$
In which of the following groups are both ions coloured in aqueous solution ?
I. $\text{Cu}^+ \qquad \qquad$ II. $\text{Ti}^{4+} \qquad \qquad$ III. $\text{Co}^{2+} \qquad \qquad$ IV. $\text{Fe}^{2+}$
[Atomic number : $\text{Cu} = 29$, $\text{Ti} = 22$, $\text{Co} = 27$, $\text{Fe} = 26$]
(A) I and ...
Assertion ($A$) : Henry's law constant ($K_{\text{H}}$) decreases with increase in temperature.
Reason ($R$) : As the temperature increases, solubility of gases in liquids decreases.
(ii) $\Lambda^{\circ}_{ ext{m}} ext{ NH}_4 ext{Cl}$, $\Lambda^{\circ}_{ ext{m}} ext{ NaOH}$ and $\Lambda^{\circ}_{ ext{m}} ext{ NaCl}$ are $129\cdot8$, $217\cdot4$, and $108\cdot9 ext{ S cm}^2 ext{ mol}^{-1}$ respectively. Molar conductivity of $1 imes 10^{-2} ext{ M}$ solution of $ ext{NH}_4 ext{O...
The freezing point of one molal $ ext{KCl}$ solution, assuming $ ext{KCl}$ to be completely dissociated in water, is : ($K_f$ for water $= 1 \cdot 86 ext{ K kg mol}^{-1}$)
(A) $- 3 \cdot 72^\circ ext{C}$
(B) $+ 3 \cdot 72^\circ ext{C}$
(C) $- 1 \cdot 86^\circ ext{C}$
(D) $+ 2 \cdot 72^\circ ext{C}...
A solution of acetone in ethanol :
(A) obeys Raoult's law.
(B) forms an ideal solution.
(C) shows a positive deviation from Raoult's law.
(D) shows a negative deviation from Raoult's law.
State Henry's law. Why are aquatic species more comfortable in cold water as compared to warm water ?
A solution of acetone in chloroform :
(A) obeys Raoult's law.
(B) forms azeotrope.
(C) shows a positive deviation from Raoult's law.
(D) shows a negative deviation from Raoult's law.
The freezing point of one molal $ ext{KCl}$ solution, assuming $ ext{KCl}$ to be completely dissociated in water, is : ($K_{ ext{f}}$ for water = $1\cdot86 ext{ K kg mol}^{-1}$)
(A) $-3\cdot72\,^\circ ext{C}$
(B) $+3\cdot72\,^\circ ext{C}$
(C) $-1\cdot86\,^\circ ext{C}$
(D) $+2\cdot72\,^\circ ex...
State Raoult's law for a solution containing volatile components. Why is the vapour pressure of an aqueous solution of glucose lower than that of water?
The freezing point of one molal $\text{KCl}$ solution, assuming $\text{KCl}$ to be completely dissociated in water, is : ($K_f$ for water = $1\cdot86\text{ K kg mol}^{-1}$)
(A) $-3\cdot72^{\circ}\text{C}$
(B) $+3\cdot72^{\circ}\text{C}$
(C) $-1\cdot86^{\circ}\text{C}$
(D) $+2\cdot72^{\circ}\text{C}$
The strongest base in aqueous solution among the following amines is :
(A) $(\text{C}_2\text{H}_5)_2\text{NH}$
(B) $(\text{C}_2\text{H}_5)_3\text{N}$
(C) $\text{C}_2\text{H}_5\text{NH}_2$
(D) $\text{C}_6\text{H}_5\text{NH}_2$
On mixing $30\text{ mL}$ of acetone with $20\text{ mL}$ of chloroform, the total volume of solution is :
(A) equal to $10\text{ mL}$
(B) less than $50\text{ mL}$
(C) greater than $50\text{ mL}$
(D) equal to $50\text{ mL}$
We cannot measure the resistance of an ionic solution using DC because :
(A) it changes the composition of the solution.
(B) it can cause sparks and shocks.
(C) it does not affect the composition of the solution.
(D) it converts electrolytic cell to galvanic cell.
Define osmotic pressure. Why is measurement of osmotic pressure method preferred for the determination of molar masses of macromolecules such as proteins and polymers ?
Vapour pressure of pure water at $298 ext{ K}$ is $24 \cdot 8 ext{ mm Hg}$. Calculate the lowering in vapour pressure of an aqueous solution which freezes at $- 0 \cdot 3^{\circ} ext{C}$. ($ ext{K}_ ext{f}$ of water = $1 \cdot 86 ext{ K kg mol}^{-1}$)
The number of moles of $ ext{AgCl}$ precipitated when excess $ ext{AgNO}_3$ solution is mixed with one mole of $[ ext{Co}( ext{NH}_3)_3 ext{Cl}_3]$ is :
(A) 0
(B) 1
(C) 2
(D) 3
What is meant by positive deviation from Raoult's law ? Give an example. What type of azeotrope is formed by positive deviation ?
$0\cdot3\text{ g}$ of acetic acid ($ ext{Molar mass} = 60\text{ g mol}^{-1}$) dissolved in $30\text{ g}$ of benzene shows a depression in freezing point equal to $0\cdot45^{\circ}\text{C}$. Calculate the percentage association of acid if it forms a dimer in the solution.
(Given : $K_{ ext{f}}$ for b...
Which of the following solution in water will have the lowest freezing point ?
(A) $1% \text{ KCl}$
(B) $1% \text{ glucose}$
(C) $1% \text{ urea}$
(D) $1% \text{ CaCl}_2$
The number of moles of $\text{AgCl}$ precipitated when excess $\text{AgNO}_3$ solution is mixed with one mole of $[\text{Co}(\text{NH}_3)_4\text{Cl}_2]\text{Cl}$ is :
(A) $1$
(B) $0$
(C) $2$
(D) $3$
Assertion (A) : Maltose is a reducing sugar.
Reason (R) : One of the two glucose units can open to expose free aldehydic group in solution.
What is meant by negative deviation from Raoult's law ? Give an example. What type of azeotrope is formed by negative deviation ?
$0\cdot3\text{ g}$ of acetic acid (Molar mass $= 60\text{ g mol}^{-1}$) dissolved in $30\text{ g}$ of benzene shows a depression in freezing point equal to $0\cdot45^{\circ}\text{C}$. Calculate the percentage association of acid if it forms a dimer in the solution.
(Given : $K_{\text{f}}$ for benze...
Which of the following aqueous solutions will have the highest osmotic pressure ?
(A) $1% \text{ KCl}$ (B) $1% \text{ glucose}$
(C) $1% \text{ urea}$ (D) $1% \text{ CaCl}_2$
The number of moles of $\text{AgCl}$ precipitated when excess $\text{AgNO}_3$ solution is mixed with one mole of $[\text{Co}(\text{NH}_3)_6]\text{Cl}_3$ is :
(A) $0$
(B) $3$
(C) $6$
(D) $4$
(a) A and B liquids on mixing show rise in temperature. Which type of deviation from Raoult's law is there and why?
(b) Why can azeotropic mixture not be separated by fractional distillation?
$0.3 ext{ g}$ of acetic acid ($ ext{Molar mass} = 60 ext{ g mol}^{-1}$) dissolved in $30 ext{ g}$ of benzene shows a depression in freezing point equal to $0.45^\circ ext{C}$. Calculate the percentage association of acid if it forms a dimer in the solution.
(Given : $K_{ ext{f}}$ for benzene $= 5.12...
(b) (i) What type of deviation from Raoult's law is expected when phenol and aniline are mixed with each other ? What change in the net volume of the mixture and enthalpy is expected ?
(ii) Boiling point of water at $750\text{ mmHg}$ is $99\cdot48^{\circ}\text{C}$. How much sucrose ($ ext{M} = 342\t...
a. Nitrogen gas is soluble in water. At temperature $293\text{ K}$, the value of $K_\text{H}$ is $76.48\text{ kbar}$. How would the solubility of nitrogen vary (increase, decrease or remain the same) at a temperature above $293\text{ K}$, if the value of $K_\text{H}$ rises to $88.8\text{ kbar}$.
b. ...
a. Write down the reaction occurring on two inert electrodes when electrolysis of copper chloride is done. What will happen if a concentrated solution of copper sulphate is replaced with copper chloride?
a. An experiment was carried out in the laboratory, to study depression in freezing point. 1M aqueous solution of $\text{Al(NO}_3)_3$ and 1 M aqueous solution of glucose were taken. From the given figure identify solution 1 and solution 2. Give a plausible reason for your answer.
b. The osmotic pressure of a solution of cane sugar was found to be 2.46 atm at 300 K. If the solution was diluted five times, calculate the osmotic pressure at the same temperature. How can the osmotic pressure of the given cane sugar solution be decreased without changing its volume? Give a reason...
While giving intravenous injections to the patients, the doctors take utmost care of the concentration of the solution used. Why is it necessary to check the concentration of the solution?
(for visually challenged learners) Which of the two solutions : $1 ext{M}$ aqueous solution of $ ext{Al(NO}_3)_3$ or $1 ext{M}$ aqueous solution of glucose will show a greater depression in freezing point? Give a plausible reason for your answer.
(for visually challenged learners) The osmotic pressure of a solution of cane sugar was found to be $2.46 ext{ atm}$ at $300 ext{ K}$. If the solution was diluted five times, calculate the osmotic pressure at the same temperature. How can the osmotic pressure of the given cane sugar solution be decr...
OR: While giving intravenous injections to the patients, the doctors take utmost care of the concentration of the solution used. Why is it necessary to check the concentration of the solution?
Assertion (A) : Chloroform and acetone mixture shows negative deviation from Raoult's law. Reason (R) : In chloroform and acetone mixture, A - A or B - B type intermolecular interactions are weaker than A - B type interactions.
State Henry's law and write its two applications.
(a) Give the IUPAC name and electronic configuration of central metal atom in terms of $t_{2g}$ and $e_g$ of $\text{K}_4[\text{Mn(CN)}_6]$.
(b) How many ions are produced from the complex $[\text{Cr(NH}_3)_6] \text{ Cl}_2$ in solution ?
A 1% solution of solute 'X' is isotonic with a 6% solution of sucrose (molar mass = 342 $\text{g mol}^{-1}$). The molar mass of solute 'X' is :
(A) 34.2 $\text{g mol}^{-1}$
(B) 57 $\text{g mol}^{-1}$
(C) 114 $\text{g mol}^{-1}$
(D) 3.42 $\text{g mol}^{-1}$
A solution is prepared by dissolving $5\text{ g}$ of a non-volatile solute in $200\text{ g}$ of water. It has a vapour pressure of $31\cdot84\text{ mm Hg}$ at $300\text{ K}$. Calculate the molar mass of the solute.
(Vapour pressure of pure water at $300\text{ K} = 32\text{ mm Hg}$)
(a) (i) Calculate emf of the following cell at 25°C :
Zn (s) | Zn^{2+} (0.001M) || Cd^{2+} (0.1 M) | Cd (s)
Given : E^{o}_{Zn^{2+}/Zn} = -0.76 V, E^{o}_{Cd^{2+}/Cd} = -0.40 V [log 10 = 1]
(ii) State Faraday's second law of electrolysis. How will the pH of aqueous NaCl solution be affected when it i...
Assertion (A) : $\Delta_{\text{mix}}\text{H}$ and $\Delta_{\text{mix}}\text{V}$ are zero for non-ideal solutions.
Reason (R) : Solute-solvent interactions are not same as pure solute-solute and pure solvent-solvent interactions in non-ideal solutions.
A solution is prepared by dissolving 5 g of a non-volatile solute in 200 g of water. It has a vapour pressure of $31\cdot84$ mm Hg at 300 K. Calculate the molar mass of the solute. (Vapour pressure of pure water at 300 K = 32 mm Hg)
(a) (i) Calculate emf of the following cell at 25°C : $\text{Zn (s) | Zn}^{2+} (0.001\text{M) || Cd}^{2+} (0.1 \text{M) | Cd (s)}$ Given : $\text{E}^o_{\text{Zn}^{2+}/\text{Zn}} = -0.76 \text{ V, E}^o_{\text{Cd}^{2+}/\text{Cd}} = -0.40 \text{ V}$ [log 10 = 1] (ii) State Faraday's second law of elect...
On adding $\text{AgNO}_3$ solution to 1 mole of $\text{CoCl}_3 \cdot 4\text{NH}_3$, one mole of $\text{AgCl}$ is precipitated. The secondary valency of Co is :
(A) 6
(B) 4
(C) 3
(D) 7
Assertion (A) : $\Delta_{\text{mix}}H$ and $\Delta_{\text{mix}}V$ are zero for an ideal solution. Reason (R) : The solution which obeys Raoult's law over the entire range of concentration is called an ideal solution.
A solution is prepared by dissolving 5 g of a non-volatile solute in 200 g of water. It has a vapour pressure of 31.84 mm Hg at 300 K. Calculate the molar mass of the solute.
(Vapour pressure of pure water at 300 K = 32 mm Hg)
(ii) State Faraday's second law of electrolysis. How will the pH of aqueous NaCl solution be affected when it is electrolysed ?
(a) Draw the geometrical isomers of the complex $[\text{Pt}(\text{NH}_3)_2\text{Cl}_2]$.
(b) Give the electronic configuration of $d^4$ ion when $\Delta_o > P$.
(c) Solution of $[\text{Ni}(\text{H}_2\text{O})_6]^{2+}$ is green in colour whereas $[\text{Ni}(\text{CN})_4]^{2-}$ is colourless. Give rea...
(c) (i) The vapour pressure of pure benzene at a certain temperature is $1.25$ atm. When $1.2$ g of non-volatile, non-electrolyte solute is added to $60$ g of benzene ($M = 78$ g mol$^{-1}$), the vapour pressure of the solution becomes $1.237$ atm. Calculate the molar mass of the non-volatile solute...
(c) (ii) The boiling point of benzene is $353.23$ K. When $1.80$ g of a non-volatile solute was dissolved in $90$ g of benzene, the boiling point is raised to $354.11$ K. Calculate the molar mass of the solute. $K_b$ for benzene is $2.53$ K kg mol$^{-1}$.
Attempt any five of the following: (a) $\text{Cu}^+$ is not stable in aqueous solution. Comment.
Calculate elevation of the boiling point of solution when 2 g of $\text{MgSO}_4$ (molar mass = 120 g/mol) was dissolved in 100 g of water, assuming $\text{MgSO}_4$ undergoes complete dissociation. [$\text{K}_b$ for water = 0.52 K kg mol$^{-1}$]
The cause for deviation from Raoult's law in the colligative properties of non-ideal solutions lie in the nature of interactions at the molecular level. These properties show deviations from Raoult's law due to difference in interactions between solute - solvent, solute - solute and solvent - solven...
(a) Draw the geometrical isomers of the complex $[\text{Pt}(\text{NH}_3)_2\text{Cl}_2]$. (b) Give the electronic configuration of $\text{d}^4$ ion when $\Delta_\text{o} > \text{P}$. (c) Solution of $[\text{Ni}(\text{H}_2\text{O})_6]^{2+}$ is green in colour whereas $[\text{Ni}(\text{CN})_4]^{2-}$ is...
(c) (i) The vapour pressure of pure benzene at a certain temperature is $1.25 \text{ atm}$. When $1.2 \text{ g}$ of non-volatile, non-electrolyte solute is added to $60 \text{ g}$ of benzene ($M = 78 \text{ g mol}^{-1}$), the vapour pressure of the solution becomes $1.237 \text{ atm}$. Calculate the...
(c) (ii) The boiling point of benzene is $353.23 \text{ K}$. When $1.80 \text{ g}$ of a non-volatile solute was dissolved in $90 \text{ g}$ of benzene, the boiling point is raised to $354.11 \text{ K}$. Calculate the molar mass of the solute. $K_b$ for benzene is $2.53 \text{ K kg mol}^{-1}$.
(a) (ii) Calculate the time to deposit $1.5 \text{ g}$ of silver at cathode when a current of $1.5 \text{ A}$ was passed through the solution of $\text{AgNO}_3$. [Molar mass of $\text{Ag} = 108 \text{ g mol}^{-1}$, $1 \text{ F} = 96500 \text{ C mol}^{-1}$]
Why does a solution containing non-volatile solute have higher boiling point than a pure solvent ? Why is elevation of boiling point a colligative property ?
Calculate the boiling point of the solution when 4 g of $\text{MgSO}_4$ ($\text{M} = 120 \text{ g mol}^{-1}$) was dissolved in 100 g of water, assuming $\text{MgSO}_4$ undergoes complete ionization. ($K_b$ for water = $0.52 \text{ K kg mol}^{-1}$)
Assertion (A) : Osmotic pressure is a colligative property.
Reason (R) : Osmotic pressure is proportional to the molality.
The vapour pressure of pure liquid X and pure liquid Y at 25 °C are 120 mm Hg and 160 mm Hg respectively. If equal moles of X and Y are mixed to form an ideal solution, calculate the vapour pressure of the solution.
(a) On diluting two electrolytes 'A' and 'B', the $\wedge_m$ of 'A' increases 25 times while that of 'B' increases by 1.5 times. Which of the two electrolytes is strong ? Justify your answer graphically.
OR
(b) The electrical resistance of a column of $0.05 \text{ mol L}^{-1} \text{ NaOH}$ solution ...
(a) Differentiate between Ideal solution and Non-ideal solution. (b) $30 \text{ g}$ of urea is dissolved in $846 \text{ g}$ of water. Calculate the vapour pressure of water for this solution if vapour pressure of pure water at $298 \text{ K}$ is $23\cdot8 \text{ mm Hg}$.
(a) (i) Carry out the following conversions : (1) Ethanal to But-2-en-1-al (2) Propanoic acid to 2-chloropropanoic acid (ii) An alkene with molecular formula $\text{C}_5\text{H}_{10}$ on ozonolysis gives a mixture of two compounds 'B' and 'C'. Compound 'B' gives positive Fehling test and also reacts...
Assertion (A) : $(\text{C}_2\text{H}_5)_2\text{NH}$ is more basic than $(\text{C}_2\text{H}_5)_3\text{N}$ in aqueous solution.
Reason (R) : In $(\text{C}_2\text{H}_5)_2\text{NH}$, there is more steric hindrance and $+I$ effect than $(\text{C}_2\text{H}_5)_3\text{N}$.
A solution is prepared by dissolving 10 g of non-volatile solute in 200 g of water. It has a vapour pressure of 31.84 mm Hg at 308 K. Calculate the molar mass of the solute. (Vapour pressure of pure water at 308 K = 32 mm Hg)
(a) On diluting two electrolytes 'A' and 'B', the $\Lambda_m$ of 'A' increases 25 times while that of 'B' increases by 1.5 times. Which of the two electrolytes is strong ? Justify your answer graphically. OR (b) The electrical resistance of a column of $0.05 \text{ mol L}^{-1}$ $\text{NaOH}$ solutio...
Give reason :
(a) Measurement of osmotic pressure method is preferred for the determination of molar masses of macromolecules such as proteins and polymers.
(b) Aquatic animals are more comfortable in cold water than in warm water.
(c) Elevation of boiling point of $1 \text{ M KCl}$ solution is near...
On dissolving ammonium chloride in water at room temperature, the solution feels cool to touch. Under which of the following conditions does salt dissolve faster?
(a) Powdered salt in cold water
(b) Powdered salt in hot water
(c) Salt crystals in cold water
(d) Salt crystals in hot water
(a) Calculate $\Delta_r \text{G}^{\circ}$ for the cell reaction at $25^{\circ}\text{C}$ : $\text{Zn} \mid \text{Zn}^{2+} \parallel \text{Cd}^{2+} \mid \text{Cd}$ Given that : $\text{E}^{\circ}_{\text{Zn}^{2+}/\text{Zn}} = -0.76 \text{ V}$, $\text{E}^{\circ}_{\text{Cd}^{2+}/\text{Cd}} = 0.40 \text{ V...
(a) Differentiate between Ideal solution and Non-ideal solution.
(b) 30 g of urea is dissolved in 846 g of water. Calculate the vapour pressure of water for this solution if vapour pressure of pure water at 298 K is 23.8 mm Hg.
In which of the following solvents, the $\text{C}_4\text{H}_9\text{NH}_3^+\text{X}^-$ is soluble;
(a) ether (b) acetone (c) water (d) bromine water
Given below are two statements labelled as Assertion (A) and Reason (R)
Assertion (A): During electrolysis of aqueous copper sulphate solution using copper electrodes hydrogen gas is released at the cathode.
Reason (R): The electrode potential of $\text{Cu}^{2+} / \text{Cu}$ is greater than that of ...
A 5% solution of $\text{Na}_2\text{SO}_4 \cdot 10\text{H}_2\text{O}$ (MW = 322) is isotonic with 2% solution of non-electrolytic, non volatile substance X. Find out the molecular weight of X.
You are given four organic compounds "A", "B", "C" and "D". The compounds "A", "B" and "C" form an orange-red precipitate with 2,4 DNP reagent. Compounds "A" and "B" reduce Tollen's reagent while compounds "C" and "D" do not. Both "B" and "C" give a yellow precipitate when heated with iodine in the ...
(a) What is the effect of temperature on the solubility of glucose in water?
(b) Ibrahim collected a $10$mL each of fresh water and ocean water. He observed that one sample labeled "P" froze at $0$ °C while the other "Q" at $-1.3$ °C. Ibrahim forgot which of the two, "P" or "Q" was ocean water. Help...
An azeotropic mixture of two liquids will have a boiling point lower than either of the two liquids when it
(a) shows a negative deviation from Raoult's law
(b) forms an ideal solution
(c) shows a positive deviation from Raoult's law
(d) is saturated
Assertion (A) : Elevation in boiling point is a colligative property.
Reason (R) : The lowering of vapour pressure of solution causes elevation in boiling point.
The vapour pressure of pure liquid X and pure liquid Y at $25^{\circ}\text{C}$ are $120$ mm Hg and $160$ mm Hg respectively. If equal moles of X and Y are mixed to form an ideal solution, calculate the vapour pressure of the solution.
Solubility of gas in liquid decreases with increase in
(a) Pressure
(b) Temperature
(c) Volume
(d) Number of solute molecules
The reagent that can be used to distinguish acetophenone and benzophenone is (a) 2, 4-dinitrophenyl hydrazine (b) aqueous $\text{NaHSO}_3$ (c) Fehling solution (d) $\text{I}_2$ and $\text{NaOH}$
Which of the following compounds will undergo self-condensation in the presence of dilute $\text{NaOH}$ solution ? (a) $\text{C}_6\text{H}_5\text{CHO}$ (b) $\text{CH}_3\text{CH}_2\text{CHO}$ (c) $(\text{CH}_3)_3\text{C} - \text{CHO}$ (d) $\text{H} - \text{CHO}$
Assertion (A) : The enthalpy of mixing $\Delta_{\text{mix}} \text{H}$ is equal to zero for an ideal solution.
Reason (R) : For an ideal solution the interaction between solute and solvent molecules is stronger than the interactions between solute-solute or solvent-solvent molecules.
The vapour pressure of pure liquid X and pure liquid Y at $25\ ^\circ\text{C}$ are $120\ \text{mm Hg}$ and $160\ \text{mm Hg}$ respectively. If equal moles of X and Y are mixed to form an ideal solution, calculate the vapour pressure of the solution.
For an electrolyte undergoing dissociation in an aqueous solution the Van't Hoff factor :
(a) is always less than one.
(b) is always greater than one.
(c) has zero value.
(d) has negative value.
Assertion (A) : Molarity of solution in liquid state changes with temperature.
Reason (R) : The volume of a solution changes with change in temperature.
What type of deviation from Raoult's law is shown by chloroform and acetone solution ? Give reason.
The freezing point of a solution containing 5 g of benzoic acid ($M = 122 \text{ g mol}^{-1}$) in 35 g of benzene is depressed by 2.94 K. What is the percentage association of benzoic acid if it forms a dimer in solution ?
($K_f$ for benzene = 4.9 $\text{K kg mol}^{-1}$)
Which of the following colligative property is used to find the molar mass of proteins ? (a) Osmotic pressure (b) Elevation in boiling point (c) Depression in freezing point (d) Relative lowering of vapour pressure
How many ions are produced in the solution from the complex $[\text{Ni}(\text{NH}_3)_6]\text{Cl}_2$ ? (a) 4 (b) 3 (c) 2 (d) 5
Assertion (A) : Electrolysis of aqueous solution of $\text{NaCl}$ gives chlorine gas at anode instead of oxygen gas.
Reason (R) : Formation of oxygen gas at anode requires overpotential.
Account for the following :
(1) Transition metals form complex compounds.
(2) The $\text{E}^{\circ}_{\text{Mn}^{2+}/\text{Mn}}$ value for manganese is highly negative whereas $\text{E}^{\circ}_{\text{Mn}^{3+}/\text{Mn}^{2+}}$ is highly positive.
(3) $\text{Cu}^{+}$ ion is unstable in aqueous solutio...
0.3 g of acetic acid ($M = 60 \text{ g mol}^{-1}$) dissolved in 30 g of benzene shows a depression in freezing point equal to $0.45^{\circ}\text{C}$. Calculate the percentage association of acid if it forms a dimer in the solution. (Given : $\text{K}_\text{f}$ for benzene = $5.12 \text{ K kg mol}^{-...
Isotonic solutions have : (a) same osmotic pressure (b) same boiling point (c) same melting point (d) same vapour pressure
Assertion (A): Electrolysis of aqueous solution of NaCl gives chlorine gas at anode instead of oxygen gas.
Reason (R): Formation of oxygen gas at anode requires overpotential.
On mixing liquid X and liquid Y, volume of the resulting solution decreases. What type of deviation from Raoult's law is shown by the resulting solution? What change in temperature would you observe after mixing liquids X and Y?
$0.3 \text{ g}$ of acetic acid (M = $60 \text{ g mol}^{-1}$) dissolved in $30 \text{ g}$ of benzene shows a depression in freezing point equal to $0.45^\circ\text{C}$. Calculate the percentage association of acid if it forms a dimer in the solution. (Given : $\text{K}_f$ for benzene = $5.12 \text{ K...
(a) (i) Account for the following : (1) Transition metals form complex compounds. (2) The $E^{\circ}_{\text{Mn}^{2+}/\text{Mn}}$ value for manganese is highly negative whereas $E^{\circ}_{\text{Mn}^{3+}/\text{Mn}^{2+}}$ is highly positive. (3) $\text{Cu}^{+}$ ion is unstable in aqueous solution. (ii...
Which one of the following pairs will not form an ideal solution ?
(a) Benzene and Toluene
(b) Nitric acid and Water
(c) Hexane and Heptane
(d) Ethyl chloride and Ethyl bromide
0.3 g of acetic acid (M = 60 g mol$^{-1}$) dissolved in 30 g of benzene shows a depression in freezing point equal to 0.45 $^{\circ}\text{C}$. Calculate the percentage association of acid if it forms a dimer in the solution.
(Given : $\text{K}_\text{f}$ for benzene = 5.12 K kg mol$^{-1}$)
(a) (i) Account for the following : (1) Transition metals form complex compounds. (2) The $E^\circ_{ ext{Mn}^{2+}/ ext{Mn}}$ value for manganese is highly negative whereas $E^\circ_{ ext{Mn}^{3+}/ ext{Mn}^{2+}}$ is highly positive. (3) $ ext{Cu}^+$ ion is unstable in aqueous solution. (ii) Write the...
A compound undergoes complete tetramerization in a given organic solvent. The Van't Hoff factor 'i' is : (a) 4.0 (b) 0.25 (c) 0.125 (d) 2.0
(i) Name two oxometal anions of the 3d series of the transition metals in which the metal exhibits the oxidation state equal to its group number. (ii) What is the effect of increasing pH on a solution of $\text{K}_2\text{Cr}_2\text{O}_7$? (iii) Why is $\text{Cu}^+$ not stable in aqueous solution? (i...
Assertion (A) : $\Lambda_{\text{m}}$ for weak electrolytes shows a sharp decrease when the electrolytic solution is diluted. Reason (R) : For weak electrolytes, degree of dissociation increases with dilution of solution.
A compound undergoes complete dimerization in a given organic solvent. The Van't Hoff factor 'i' is : (a) 2.0 (b) 0.5 (c) 0.25 (d) 1.0
The number of faradays passed through a solution of $\text{CuSO}_4$ to produce 1 mol of Cu and $\text{O}_2$ will be : (a) 1.0 (b) 4.0 (c) 8.0 (d) 2.0
Assertion (A) : $\Lambda_{\text{m}}$ for weak electrolytes shows a sharp increase when the electrolytic solution is diluted. Reason (R) : For weak electrolytes, degree of dissociation decreases with dilution of solution.
A compound $\text{CaCl}_2 \cdot 6\text{H}_2\text{O}$ undergoes complete dissociation in water. The Van't Hoff factor 'i' is :
(a) 9
(b) 6
(c) 3
(d) 4
Assertion (A) : When NaCl is added to water, a depression in freezing point is observed.
Reason (R) : The vapour pressure of solution is increased which causes depression in freezing point.
1 mole of liquid A and 2 moles of liquid B make a solution having a total vapour pressure 40 torr. The vapour pressure of pure A and pure B are 45 torr and 30 torr respectively. The above solution
(a) is an ideal solution.
(b) shows positive deviation.
(c) shows negative deviation.
(d) is a maximum ...
If molality of a dilute solution is doubled, the value of the molal elevation constant ($\text{K}_b$) will be
(a) halved
(b) doubled
(c) tripled
(d) unchanged
Nucleophilic Substitution
Nucleophilic Substitution reaction of haloalkane can be conducted according to both $S_N1$ and $S_N2$ mechanisms. $S_N1$ is a two step reaction while $S_N2$ is a single step reaction. For any haloalkane which mechanism is followed depends on factors such as structure of hal...
(c) Amit, a classmate of Rahul repeated the same experiment with $\text{CH}_3\text{COOH}$ solution instead of $\text{KCl}$ solution. Give one point that would be similar and one that would be different in his observations as compared to Rahul.
(a) (i) Why is boiling point of 1M $\text{NaCl}$ solution more than that of 1M glucose solution ? (ii) A non-volatile solute 'X' (molar mass = 50 $\text{g mol}^{-1}$) when dissolved in 78g of benzene reduced its vapour pressure to 90%. Calculate the mass of X dissolved in the solution. (iii) Calcula...
Which of the following aqueous solution will have highest boiling point ?
(a) 1.0 M KCl
(b) 1.0 M K$_2$SO$_4$
(c) 2.0 M KCl
(d) 2.0 M K$_2$SO$_4$
Nucleophilic Substitution reaction of haloalkane can be conducted according to both $S_N1$ and $S_N2$ mechanisms. $S_N1$ is a two step reaction while $S_N2$ is a single step reaction. For any haloalkane which mechanism is followed depends on factors such as structure of haloalkane, properties of lea...
(a) (i) Why is boiling point of $1 ext{M NaCl}$ solution more than that of $1 ext{M}$ glucose solution? (ii) A non-volatile solute 'X' (molar mass = $50 ext{ g mol}^{-1}$) when dissolved in $78 ext{g}$ of benzene reduced its vapour pressure to $90%$. Calculate the mass of X dissolved in the solution...
Assertion (A) : $[\text{Co}(\text{NH}_3)_5 \text{SO}_4] Cl$ gives a white precipitate with silver nitrate solution.
Reason (R) : The complex dissociates to give $Cl^-$ and $\text{SO}_4^{2-}$ ions.
(a) (i) Why is boiling point of $1\text{M} \text{NaCl}$ solution more than that of $1\text{M}$ glucose solution? (ii) A non-volatile solute 'X' (molar mass = $50 \text{ g mol}^{-1}$) when dissolved in $78\text{g}$ of benzene reduced its vapour pressure to $90%$. Calculate the mass of X dissolved in ...
(i) Why is the value of Van't Hoff factor for ethanoic acid in benzene close to 0.5 ?
(ii) Determine the osmotic pressure of a solution prepared by dissolving $2.32 \times 10^{-2}\text{g}$ of $\text{K}_2\text{SO}_4$ in 2L of solution at 25 °C, assuming that $\text{K}_2\text{SO}_4$ is completely diss...
(a) On the basis of crystal field theory, write the electronic configuration for $d^4$ with a strong field ligand for which $\Delta_0 > P$. (b) A solution of $[\text{Ni}(\text{H}_2\text{O})_6]^{2+}$ is green but a solution of $[\text{Ni}(\text{CO})_4]$ is colourless. Explain. [Atomic number : Ni = 2...
OR (c) Amit a classmate of Rahul repeated the same experiment with $\text{CH}_3\text{COOH}$ solution instead of $\text{KCl}$ solution. Give one point that would be similar and one that would be different in his observations as compared to Rahul.
(a) Find the value of van't Hoff factor for acetic acid in benzene as per the given equation : 2CH$_{3}$COOH $\rightleftharpoons$ (CH$_{3}$COOH)$_{2}$, assuming its complete association. (b) Osmotic pressure of a solution containing 3.5 g of dissolved protein in 0.05 L of a solution is 0.035 atm at ...
(b) Which of the following show positive deviation from Raoult's law? Carbon disulphide and Acetone; Phenol and Aniline; Ethanol and Acetone
OR (c) The boiling point of solution increases when $1\text{ mol}$ of $\text{NaCl}$ is added to $1$ litre of water while addition of $1\text{ mol}$ of methanol to one litre of water decreases its boiling point. Explain the above observations.
Three compounds are given below :
$ ext{C}_2 ext{H}_5 ext{NH}_2$, $( ext{C}_2 ext{H}_5)_2 ext{NH}$, $( ext{C}_2 ext{H}_5)_3 ext{N}$
I II III
The correct decreasing order of their basic strength in an aqueous solution is :
(a) II > III > I (b) III > II > I
(c) I > II > III (d) I > III > II
(a) Find the van't Hoff factor for aqueous $\text{KCl}$, assuming complete dissociation. (b) A solution of an organic compound is prepared by dissolving $68\cdot4\text{ g}$ in $1000\text{ g}$ of water. Calculate the molar mass of the compound when elevation in boiling point is $0\cdot104\text{ K}$ a...
(b) Which of the following show positive deviation from Raoult's law ? Carbon disulphide and Acetone; Phenol and Aniline; Ethanol and Acetone
(c) The vapour pressure of a solution of glucose in water is $750 \text{ mm Hg}$ at $100^{\circ}\text{C}$. Calculate the mole fraction of solute. (Vapour pres...
(a) What will be the van't Hoff factor for a dilute solution of $\text{K}_2\text{SO}_4$, assuming complete dissociation? (b) $1.00\text{ g}$ of non-electrolyte solute dissolved in $50\text{ g}$ of benzene lowered the freezing point of benzene by $0.40\text{ K}$. Find the molar mass of the solute. ($...
A solution that obeys Raoult's law is called :
(a) a non-ideal solution
(b) a molar solution
(c) an ideal solution
(d) a saturated solution
Which of the following transition metal ions is a strong oxidising agent in aqueous solution ?
(a) $\text{Zn}^{2+}$
(b) $\text{Mn}^{2+}$
(c) $\text{Mn}^{3+}$
(d) $\text{Cr}^{2+}$
The osmotic pressure of a solution increases if the:
(a) number of solute molecules is increased.
(b) temperature is decreased.
(c) volume is increased.
(d) number of solute molecules is decreased.
What type of deviation from Raoult's law is shown by ethanol and acetone mixture? Give reason.
Calculate the boiling point of solution when $4\text{ g}$ of $\text{MgSO}_4$ ($M = 120\text{ g mol}^{-1}$) was dissolved in $100\text{ g}$ of water, assuming $\text{MgSO}_4$ undergoes complete dissociation. ($K_b$ for water = $0\cdot52\text{ K kg mol}^{-1}$)
Following ions of 3d-transition series are given :
Ti^{4+}, V^{3+}, Cr^{3+}, Mn^{3+}
(Atomic number : Ti = 22, V = 23, Cr = 24, Mn = 25)
Identify the ion which is
(i) most stable in aqueous solution.
(ii) a strong oxidising agent.
(iii) colourless in aqueous solution.
Give suitable reason in each.
Out of the following pairs, predict with reason which will allow greater conduction of electricity :
(i) 1M $\text{CH}_3\text{COOH}$ solution or 0.1M $\text{CH}_3\text{COOH}$ solution on dilution.
(ii) Copper wire at 27 °C or Copper wire at 50 °C.
Following ions of 3d transition series are given :
$\text{V}^{3+}, \text{Cr}^{2+}, \text{Cu}^{+}, \text{Fe}^{2+},$
(Atomic number : $\text{V} = 23, \text{Cr} = 24, \text{Cu} = 29, \text{Fe} = 26$)
Identify the ion which is
(a) unstable in aqueous solution.
(b) a strong reducing agent in aqueous solu...
Following ions of 3d transition series are given:
$ ext{Ti}^{2+}, ext{Fe}^{2+}, ext{Cu}^{2+}, ext{Zn}^{2+}$
(Atomic number: $ ext{Ti} = 22, ext{Fe} = 26, ext{Cu} = 29, ext{Zn} = 30$)
Identify the ion, which is
(i) a strong reducing agent in aqueous solution.
(ii) more stable than its...
Henna is investigating the melting point of different salt solutions. She makes a salt solution using 10 mL of water with a known mass of NaCl salt. She puts the salt solution into a freezer and leaves it to freeze. She takes the frozen salt solution out of the freezer and measures the temperature w...
Define conductivity for the solution of an electrolyte. Why does the conductivity of a solution decrease with dilution ?
Account for the following : (i) $\text{Cr}^{2+}$ is a strong reducing agent. (ii) $\text{Ti}^{3+}$ is coloured whereas $\text{Sc}^{3+}$ is colourless in aqueous solution. (iii) $\text{Zn}$, $\text{Cd}$ and $\text{Hg}$ are not called transition elements.
OR
(I) Define the following terms :
(i) Zeta Potential
(ii) Coagulation
(II) Why a negatively charged sol is obtained when $AgNO_3$ solution is added to $KI$ solution ?
(i) What will happen to the concentration of $\text{Zn}^{2+}$ and $\text{Ag}^{+}$ when $E_{\text{cell}} = 0$.
(ii) Why does conductivity of a solution decreases with dilution?
(i) The electronic configuration of Ce is: $_{58}\text{Ce} = [\text{Xe}]^{54} 4f^1 5d^1 6s^2. Calculate the spin only magnetic moment of $\text{Ce}^{3+}$ ion.
(ii) Why is copper regarded as a transition element although copper atom has completely filled d-orbitals in its ground state?
(iii) Why is $...
(b) (i) The electronic configuration of $\text{Ce}$ is :
${}_{58}\text{Ce} = [\text{Xe}]^{54}\text{ } 4\text{f}^1 \text{ } 5\text{d}^1 \text{ } 6\text{s}^2$
Calculate the spin only magnetic moment of $\text{Ce}^{3+}$ ion.
(ii) Why is copper regarded as a transition element although copper atom has c...
Account for the following : (i) Transition metals and their compounds show catalytic activities. (ii) $\text{Cu}^{2+}$ is coloured while $\text{Cu}^{+}$ is colourless in aqueous solution. (iii) $E^{\circ}$ value for $\text{Mn}^{2+}/\text{Mn}$ couple is highly negative.