Question

Explain why is sodium less reactive than potassium.

Answer 1

Potassium has lower ionization enthalpy (496 kJ/mol) than sodium (520 kJ /mol).
Thus, the ease with which K loses an electron is higher than the ease with which Na loses an electron. Hence, sodium is less reactive than potassium. The standard reduction potential of potassium (-2.925 V) is more negative than that of sodium (-2.714 V). This also indicates lower reactivity of sodium as compared to potassium.