MolSynapsequestion bank
MolSynapse / Question bank / Environmental Chemistry / Water pollution, BOD and COD
JEE Main levelSingle correct optionDifficulty 2 of 3ev135

Assertion (A): Cold water usually contains more dissolved oxygen than warm water. Reason (R): The solubility of gases in water increases as the temperature rises.

  1. ABoth A and R are true but R is not the correct explanation of A
  2. BA is true but R is false
  3. CBoth A and R are true and R is the correct explanation of A
  4. DA is false but R is true

Answer: B

Gas solubility in water decreases with a rise in temperature, so R is false. As a result cold water holds more dissolved oxygen, and A is true.
Practice Environmental Chemistry More on Water pollution, BOD and COD
Previous questionNext question

More questions on Water pollution, BOD and COD