Question

Place the elements in each set in order of increasing ionization energy.
a. F, Cl, Br
b. Na, Cl, Al
c. Na, K, Cs
d. As, Ca, Br

Short answer

Part(a) Order of increasing ionization energy is$\mathrm{Br}<\mathrm{Cl}<\mathrm{F}$

Part(b) Order of increasing ionization energy is $\mathrm{Na}<\mathrm{Al}<\mathrm{Cl}$

Part(c) Order of increasing ionization energy is $\mathrm{Cs}<\mathrm{K}<\mathrm{Na}$

Part(d) Order of increasing ionization energy is $\mathrm{Ca}<\mathrm{As}<\mathrm{Br}$

Step-by-step solution

Part(a) Step 1 : Given information

We are given F, Cl, Br elements. We have to arrange element in order of increasing ionization energy.

Part(a) Step 2 : Simplify  

When we know from the periodic table, from left to right in the ionization, no energy diminishes or increases as the nuclear charge increases.
The ionization energy increases as the electrons come closer to the nuclear charge in the nucleus from bottom to top.
As a result, the increasing ionization energy order is
$\mathrm{Br}<\mathrm{Cl}<\mathrm{F}$

Part(b) Step 1 : Given information

We are given Na, Cl, Al elements. We have to arrange element in order of increasing ionization energy.

Part(b) Step 2 : Simplify  

When we know from the periodic table, from left to right in the ionization, no energy diminishes or increases as the nuclear charge increases.
The ionization energy increases as the electrons come closer to the nuclear charge in the nucleus from bottom to top.
As a result, the increasing ionization energy order is$\mathrm{Na}<\mathrm{Al}<\mathrm{Cl}$

Part(c) Step 1 : Given information

We are given Na, K, Cs elements. We have to arrange element in order of increasing ionization energy.

Part(c) Step 2 : Simplify  

When we know from the periodic table, from left to right in the ionization, no energy diminishes or increases as the nuclear charge increases.
The ionization energy increases as the electrons come closer to the nuclear charge in the nucleus from bottom to top.
As a result, the increasing ionization energy order is$\mathrm{Cs}<\mathrm{K}<\mathrm{Na}$

Part(d) Step 1 : Given information

We are given As, Ca, Br elements. We have to arrange element in order of increasing ionization energy.

Part(d) Step 2 : Simplify  

When we know from the periodic table, from left to right in the ionization, no energy diminishes or increases as the nuclear charge increases.
The ionization energy increases as the electrons come closer to the nuclear charge in the nucleus from bottom to top.
As a result, the increasing ionization energy order is$\mathrm{Ca}<\mathrm{As}<\mathrm{Br}$