Question

which element has highest ionization energy
​

Answer 1

Explanation:

helium

The ionization energy decreases from top to bottom in groups, and increases from left to right across a period. Thus, helium has the largest first ionization energy, while francium has one of the lowest.

Answer 2

Answer:

Helium

Explanation:

The ionization energy decreases from top to bottom in groups, and increases from left to right across a period. Thus, helium has the largest first ionization energy, while francium has one of the lowest.