Question

1. which list arranges the elements na, li, k, rb and cs in order of increasing ionization energy (from left to right in the answer choices)? o cs, rb, k, na, li o li, na, k, rb, cs o cs, li, na, k, rb o na, li, k, rb, cs

Explanation:

Step1: Recall ionization - energy trend

Ionization energy decreases down a group.

Step2: Locate elements in group

Na, Li, K, Rb, Cs are in Group 1.

Step3: Arrange in increasing order

As we go down Group 1, ionization energy decreases. So the order is Cs < Rb < K < Na < Li for increasing ionization energy.

Answer:

Cs, Rb, K, Na, Li