Question

in each case of the following case choose the atom having the bigger size justify
1)mg(at no 12)or cl (at num 17)
2) Na(at no 11)or k(at no 19)

Answer 1

Hey mate
1) mg is bigger because going from left to right radius will decrease so in 2 period mg comes first than cl
2)K is bigger in size because going down the group radius will increase
Hope it will help you