Question

Based on their positions in the periodic table, rank the following atoms in order of increasing first ionization energy: F, Li, N, Rb

Short answer

\(Rb < Li < N < F\)

Step-by-step solution

Ionisation energy along with the group from top to bottom

Moving from top to bottom along a group in the periodic table increases the atomic size, leading to the decrease in ionization energy of the respective elements that belong to the same group.

Ionisation energy along with the period from left to right

Moving from left to right along a period in the periodic table decreases the atomic size, leading to the increase in ionization energy of the respective elements that belong to the same period.

Ranking the given elements in order of increasing the first ionization energy

Li, N, and F atoms belong to the same period. The atomic size order is as shown below:

\(Li > N > F\)

Among all the given atoms, Rb has the largest size, so it has the lowest ionization energy.

Hence, based on their position in the periodic table, the ionisation energy order of the given elements is as shown below:

\(Rb < Li < N < F\)