Question

Find out the smallest atomic size element?

• A. (a) Li
• B. (b) H
• C. (c) Na

Answer 1

The correct option is B

(b) H

Explanation of correct answer

(b) Hydrogen (H) is the correct answer

• Hydrogen has the smallest atomic mass
• It is the lightest element.
• On moving down a group atomic number increases, number of shells increases
• Hence atomic radius increases and the size of the atom increases.

Explanation of incorrect answer

(a) Lithium (Li)

• Lithium (Li) is alkali metal group1 in the periodic table
• It is the lightest of the solid elements.

(c) Sodium (Na)

• Sodium(Na) is an alkali metal group1 in the periodic table.
• It is a very soft element.

Conclusion: The smallest atomic size element is H.