Consider the following statements about the effect of temperature on the solubility of gases in liquids.
(A) The solubility of gases in liquids decreases with rise in temperature.
(B) When a gas dissolves in a liquid, the process can be considered similar to condensation, and heat is evolved.
(C) The dissolution of a gas in a liquid involves a dynamic equilibrium and so follows Le Chatelier’s principle.
(D) Aquatic species are more comfortable in warm waters rather than in cold waters.
Which of the statements given above are correct? Choose the correct answer from the options given below:
Answer & explanation
Correct answer: option 3
The correct answer is Option (3) → (A), (B) and (C) only
Dissolving a gas in a liquid is an exothermic process that reaches a dynamic equilibrium. By Le Chatelier’s principle, heating shifts this equilibrium back, so less gas stays dissolved.
(A) The solubility of gases in liquids decreases with rise in temperature. — True. This follows from the exothermic nature of dissolution.
(B) When a gas dissolves in a liquid, the process can be considered similar to condensation, and heat is evolved. — True. The gas molecules pass into the liquid phase, as in condensation, and give out heat.
(C) The dissolution of a gas in a liquid involves a dynamic equilibrium and so follows Le Chatelier’s principle. — True. Since the forward process gives out heat, a rise in temperature favours the gas leaving the liquid.
(D) Aquatic species are more comfortable in warm waters rather than in cold waters. — False. More oxygen dissolves in cold water, so aquatic species are more comfortable in cold waters.
NCERT (2026-27 edition):
1.3.2 Solubility of a Gas in a Liquid – “Solubility of gases in liquids decreases with rise in temperature. When dissolved, the gas molecules are present in liquid phase and the process of dissolution can be considered similar to condensation and heat is evolved in this process. We have learnt in the last Section that dissolution process involves dynamic equilibrium and thus must follow Le Chatelier’s Principle. As dissolution is an exothermic process, the solubility should decrease with increase of temperature.”
“…the solubility of gases increases with decrease of temperature. It is due to this reason that aquatic species are more comfortable in cold waters rather than in warm waters.”