Previous Year Papers

Download Solved Question Papers Free for Offline Practice and view Solutions Online.

Test Series

Take Zigya Full and Sectional Test Series. Time it out for real assessment and get your results instantly.

Test Yourself

Practice and master your preparation for a specific topic or chapter. Check you scores at the end of the test.

Electrochemistry

Long Answer Type

121. Define the terms equivalent and molar conductivity. What are their physical signific-ance?

196 Views

Short Answer Type

122. How is molar conductivity related to concentration of an electrolyte? How will you explain a weak and a strong electrolyte based on their conductivity values?

212 Views

123. What is corrosion? What are the factors which effect corrosions? CO₂ is always present in natural water. Explain its affect (increases, stops or no effect > on rusting of Fe.)

135 Views

124. What is a salt bridge? What is its significance?

186 Views

Long Answer Type

125.

What is corrosion? Describe the electrochemical phenomenon of rusting of iron.

294 Views

126. Explain why electrolysis of aqueous solution of NaCl gives H₂ at cathode and Cl₂ at anode. Write overall reaction.

3952 Views

Short Answer Type

127.

The following curve is obtained when molar conductivity λ_m (y-axis) is plotted against the square root of concentration C^1/2 (x-axis) for two electrolytes A and B.
(a) What can you about the nature of the two electrolytes A and B.
(b) How do you account for the increase in molar conductivity λ_m for the electrolytes A and B on dilution.

419 Views

128. How is the standard free energy change related to
(i) emf of a galvanic cell related to the reaction.
(ii) equilibrium constant of the reaction in equilibrium state?

135 Views

129. Prove that the free energy (ΔG) and the emf of an electro-chemical cell are related by
ΔG = – nFE₀.

127 Views

Long Answer Type

130. What are fuel cells? Write reaction of a oxygen-hydrogen fuel cell. Write two advantages of the use of a hydrogen-oxygen fuel cell.

A device to convert chemical energy of fuel into electrical energy is called fuel cell.

Hydrogen-oxygen fuel cell: The cell consists of three compartments separated from one another by porous electrode. The hydrogen gas is fed into one compartment and the oxygen gas is fed into another compartment. These gases then diffuse slowly through the electrodes and react with an electrolyte that is in the central compartment. The electrodes are made of a conducting material, such as graphite, with a sprinkling of platinum to act as a catalyst, and the electrolyte is an aqueous solution of a base. The reactions are
A device to convert chemical energy of fuel into electrical energy is

Advantages: (i) Fuel cells are efficient and free from pollution.
(ii) The only product in the reaction of fuel cell is water which can be removed and the astronauts of a spacecraft can drink it.

1138 Views