Question

Which of the alkali metals given below has the smallest size?

Options

• Rubidium

• Potassium

• Sodium

• Lithium

Answer 1

Lithium

Explanation:

All the given elements belong to Group 1 of the periodic table, collectively known as the alkali metals. As you move vertically down a group in the periodic table, the atomic size | increases because each successive element gains an additional electron shell. Since lithium (Li) sits at the very top of Group 1 with only two electron shells, it retains the smallest atomic size among the options.