Question

Identify the element that has the lower Ionization energy in each pair of the following.[ ](i) Mg or Na (ii) Li or O (iii) Br or F (iv) K or Br

Answer 1

Dear Student,

◆ Ionisation enthalpy -

• It is the minimum amount of energy required to remove the valence electron of an isolated neutral gaseous atom or molecule.

# Trend in ionization enthalpy -

Usually ionization enthalpy

• increases from left to right in a period
• decreases from top to bottom in a group

◆ Lower ionization enthalpy. -

(i) Mg or Na

Na < Mg because ionization enthalpy increases from left to right in a period.

(ii) Li or O

Li < O because ionization enthalpy increases from left to right in a period.

(iii) Br or F

Br < F because ionization enthalpy decreases from top to bottom in a group.

(iv) K or Br

K < Br because ionization enthalpy increases from left to right in a period.

Hope this helps you...

Answer 2

Ionization decreasing from top to bottom.

Explanation:

Ionization decreasing from top to bottom.

(i). Na has lower ionization energy because as we move from Na to Mg,

the ionization energy increases.

(ii). Li has lower ionization energy because as we move from Li to O,

the ionization energy increases.

(iii). F has lower ionization energy because as we move from F to Br, the ionization energy decreases.

(iv). K has lower ionization energy because as we move from K to Br, the ionization energy increases.

Note: Ionization goes on increasing as we move from left to right.