Question

Which of the following statements is not correct about the electron gain enthalpy?

• A. In general, the electron gain enthalpy becomes less negative in going from top to bottom in a group.
• B. The electron gain enthalpy becomes less negative in a period from left to right.
• C. The elements having stable configuration like noble gases have large positive electron gain enthalpies.
• D. Electron gain enthalpy of O or F is less than that of succeeding element.

Answer 1

Answer: (B)

The electron gain enthalpy becomes less negative in a period from left to right.

The electron gain enthalpy becomes more negative in a period from left to right. With an increase in atomic number, the effective nuclear charge increases. The attraction between the nucleus and valence electron increases. Hence, electron gain enthalpy becomes more negative.