Chemistry Answers

Calculate the pH of 0.01 M aqueous solution of sodium formate at 298 K. [Given: Ka (HCOOH) =1.7 × 10−4 at 298K] 

Calculate the degree of ionisation and the pH of a 0.01 M aqueous solution of formic acid at 298K. [Given, Ka (HCOOH) = 1.7  10−4at 298K]. 

Define solubility and give the relationship between solubility and solubility product constant for sparingly soluble salts of AB types. 

State Le- Chatelier’s principle and for the following reaction at equilibrium 2SO2(g) + O2(g) ⇌ 2SO3(g) ∆H = 198 kJ Predict the effect of i. Adding SO2(g) at equilibrium ii. Decreasing the temperature iii. Reducing the volume of the container to half iv. Adding an inert gas under conditions of constant pressure.

What are amphoteric substances? Explain with the help of suitable examples. 

Define degree of ionisation of a weak electrolyte and list the factors affecting it. 

Define equilibrium constant and for the following reaction 2NH3(g) ⇌ 2N2(g) +3H2 (g) i. Write the expression for Kc. ii. Relate Kc to Kp, and iii. Relate Kc to Kx 

Derive an expression for the entropy change for isothermal Mixing of Ideal Gases. 

Define spontaneity of a reaction and give the criteria of spontaneity of reactions in terms of i) entropy and ii) Gibbs energy. 

Describe the method for experimental determination of energy changes accompanying chemical reactions under constant volume conditions.