MolSynapsequestion bank
MolSynapse / Question bank / p-Block Elements: Groups 15 and 16 / Trends in groups 15 and 16
JEE Advanced levelSingle correct optionDifficulty 3 of 3pn016

Assertion: The electron gain enthalpy of oxygen is less negative than that of sulphur. Reason: The compact subshell of oxygen causes strong inter-electronic repulsion for the incoming electron.

  1. ABoth Assertion and Reason are true and the Reason is the correct explanation of the Assertion
  2. BBoth Assertion and Reason are true but the Reason is not the correct explanation of the Assertion
  3. CAssertion is true but Reason is false
  4. DAssertion is false but Reason is true

Answer: A

Oxygen's small size gives high electron density in the subshell, so adding another electron is opposed by strong repulsion; sulphur's larger subshell accommodates the electron more easily. Consequently S (-200 kJ/mol) is more negative than O (-141 kJ/mol), and the reason explains the assertion.
Practice p-Block Elements: Groups 15 and 16 More on Trends in groups 15 and 16
Previous questionNext question

More questions on Trends in groups 15 and 16