Question

Increasing order of density is

• A. $Li \, < \, K \, < \, Na \, < \, Rb \, < \, Cs$
• B. $Li \, < \, Na \, < \, K \, < \, Rb \, < \, Cs$
• C. $Li \, < \, Na \, < \, K \, < \, Cs \, < \, Rb$
• D. $K \, < \, Li \, < \, Na \, < \, Rb \, < \, Cs$

Answer 1

Answer: (A)

As per Lother-Meyer's curve, the atomic volume of $Cs$ is maximum among s-block elements. But atomic masses increases more rapidly than atomic volume, hence density increases along the group