, rank the following elements by increasing ionisation energy. Carbon, Aluminum, Oxygen, Potassium

Ionisation energy generally increases across a period (from left to right) on the periodic table and decreases down a group (from top to bottom). This is because as you move across a period, the number of protons in the nucleus increases, which increases the positive charge and hence the attraction for the electrons. As you move down a group, the outer electrons are further from the nucleus and are therefore less strongly attracted to it.

Here are the positions of the elements on the periodic table:

• Potassium (K) is in the 4th period, Group 1.
• Aluminum (Al) is in the 3rd period, Group 13.
• Carbon (C) is in the 2nd period, Group 14.
• Oxygen (O) is in the 2nd period, Group 16.

So, based on their positions, the order of increasing ionisation energy should be:

Potassium < Aluminum < Carbon < Oxygen