Question
Chemistry Question on Classification
The element with the lowest ionization potential is
A
Na
B
K
C
Rb
D
Cs
Answer
Cs
Explanation
Solution
lonisation potential is the amount of energy required to remove an electron from an isolated gaseous atom. Since, on moving down the group, the size of atom increases, thus the outer electron gets farther and farther away from the nucleus and hence, the less amount of energy is required to remove it. Thus, ionisation potential decreases and hence, Cs has lowest ionisation potential.