Question

example #1: ionization energy

1. which of the following elements will have the smallest ionization energy?

a) be
b) ca
c) ra
d) sr

1. which of the following elements will have the largest ionization energy?

a) al
b) cl
c) p
d) mg

Explanation:

Step1: Recall ionization - energy trend

Ionization energy decreases down a group and increases across a period.

Step2: Analyze first - question elements

Be, Ca, Sr, and Ra are in the same group (Group 2). Ra is at the bottom of the group, so it has the smallest ionization energy among them.

Step3: Analyze second - question elements

Al, Mg, P, and Cl are in the same period (Period 3). Cl is the right - most element among them. Since ionization energy increases across a period from left to right, Cl has the largest ionization energy among them.

Answer:

1. c) Ra
2. b) Cl