11.

Answer the following:
Define Raoult’s law for the elevation of the boiling point of a solution.

An ionic compound is made up of A cations and B anions. If A cations are present at the alternate corners and B anion is present on the body of the diagonal, what is the formula of the ionic compound?

What will be the vapour pressure of a solution containing 5 moles of sucrose (C₁₂H₂₂O₁₁) in 1 kg of water, if the vapour pressure of pure water is 4.57 mm ofHg?
[C = 12, H = 1, O = 16]

A 2 molal solution of sodium chloride in water causes an elevation in the boiling point of water by 1.88 K. What is the value of Van’t Hoff factor? What does it signify? [K_b = 0.52 K kg mol^-1]

(i) Write the mathematical expression relating the variation of rate constant of a reaction with temperature.

(ii) How can you graphically find the activation energy of the reaction from the above expression?

(iii) The slope of the line in the graph of log k (k = rate constant) versus 1/T is – 5841. Calculate the activation energy of the reaction.

Define Frenkel defect in solid crystal.

Explain giving reasons why: 
 Ionic solids conduct electricity in molten state, but not in solid state.

Explain giving reason:
Solution of sodium chloride has no effect on litmus, but a solution of zinc chloride turns blue litmus red.

In a crystal of diamond: 
(i) How many carbon atoms are present per unit cell?
(ii) What type of lattice does diamond crystallize in?
(iii) How many carbon atoms surround each carbon atom?
(iv) How are they arranged?

(i) What is standard hydrogen electrode? 

(ii) 0.05 M NaOH solution offered a resistance of 31.6 ohm in a conductivity cell at 298 K. If the cell constant of the cell is 0.367 cm^-1, calculate the molar conductivity of the NaOH solution.