Question

The quantum numbers for the outermost electron of an element are given below as $n = 2,l = 0,m = 0,s = + \frac{1}{2}$. The atoms is

• A. Lithium
• B. Beryllium
• C. Hydrogen
• D. Boron

Answer 1

Answer: (A)

Lithium

Answer 2

The electronic configuration must be $1s^{2}2s^{1}.$

Hence, the element is lithium $(z = 3).$