Question

Calcium is a ______ reactive metal than sodium.

Answer 1

Calcium is a less reactive metal than sodium.

Explanation:

Sodium (Na) belongs to Group 1 (alkali metals) and needs to lose only one valence electron to achieve a stable octet, which requires very little energy. Calcium (Ca) belongs to Group 2 (alkaline earth metals) and must lose two valence electrons, a process that requires significantly more ionisation energy. According to the reactivity series of metals, alkali metals are always more chemically reactive than their neighbouring alkaline earth metals.