Question

why do 1&2 ionisation energy of group 14 decrease from c to sn whereas the 3&4 ionisation energy vary irregularly.

Answer 1

hellooo.....!!

It is because as we move down a group atomic size increases..hence. .I.P decreases
Secondly as we move from left to right the nuclear charge increases so I. P increases..
When the atomic size is more the attractive force between the no clues and shells is less and wen n.c is mire the attractive force is more..

Hope this helped