MCQ
Assertion $(A)$ : Electron gain enthalpy becomes less negative as we go down a group.
Reason $(R)$ : Size of the atom increases on going down the group and the added electron would be farther from the nucleus.
  • A
    Assertion and reason both are correct statements but reason is not correct explanation for assertion.
  • Assertion and reason both are correct statements and reason is correct explanation for assertion.
  • C
    Assertion and reason both are wrong statements.
  • D
    Assertion is wrong statement but reason is correct statement.

Answer

Correct option: B.
Assertion and reason both are correct statements and reason is correct explanation for assertion.
On moving down the group, the electron gain enthalpy becomes less negative because on moving down the group the atomic size increases and the added electron lies away from the nucleus.

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