Question

Consider the following statements labelled as assertion (A) and Reason (R).

Assertion (A) : Aquatic species are more comfortable in cold water rather than in warm water.

Reason (R) : Solubility of a gas in a liquid increases with decrease in temperature.

In the light of above statements, choose the correct option.

• A. Assertion and reason both are correct statements and reason is correct explanation for assertion.
• B. Assertion and reason both are correct statements but reason is not correct explanation for assertion.
• C. Assertion is correct statement but reason is wrong statement.
• D. Assertion is wrong statement but reason is correct statement.

Answer 1

Answer: (A)

Assertion and reason both are correct statements and reason is correct explanation for assertion.

Answer 2

Aquatic animals depend on dissolved oxygen in water for respiration. Cold water holds more dissolved oxygen than warm water, making aquatic species more comfortable in cold water. The dissolution of gases in liquids is generally an exothermic process ($\Delta H_{sol} < 0$). According to Le Chatelier's principle, decreasing the temperature shifts the equilibrium towards heat release, increasing gas solubility. Thus, the reason correctly explains the assertion.