Question

Consider the elements Mg, Al, S, P and Si, the correct increasing order of their first ionization enthalpy is ______.

Options

• Al < Mg < Si < S < P

• Al < Mg < S < Si < P

• Mg < Al < Si < S < P

• Mg < Al < Si < P < S

Answer 1

Consider the elements Mg, Al, S, P and Si, the correct increasing order of their first ionization enthalpy is Al < Mg < Si < S < P.

Explanation:

When we move from group - IA to group - VII A, the ionization enthalpy generally increases from left to right. Mg with a fully filled electronic configuration is more stable, and a half-filled orbital is more stable than a partially filled orbital. Taking into account the full-filled orbital, half-filled orbital, and Z_eff (effective nuclear positive charge), the correct order of I.E. is Al < Mg < Si < S < P.