As nuclear charge increases, the nuclear attraction on the outer most electron increases and the outer electron is more firmly held. Therefore, ionization potential increases.

As nuclear charge increases, the nuclear attraction on the outer most electron increases and the outer electron is more firmly held. Therefore, ionization potential increases.
X | Y |
---|---|
1: Element with atomic number 19 | A: Group 18 [0 group] |
2: Element with electronic configuration 2 | B: Group 16 [VI A] |
3: Element with a valency of -2 | C: Group 1 [IA] |
4: Element ‘P’ which loses 3 electrons to form a cation | D: Group 17 [VII A] |
5: Element ‘Q’ in period-3 which has the highest electron affinity | E: Group 13 [III A] |