Which substance would have the greatest standard molar entropy?

NO2 (g)

N; (g)

N20

NO20

Option A

Explanation:

Standard molar entropy determines the randomness of a mole of substance. Thus, the larger and complex a molecule is, the larger will be its molar entropy.

The molar entropy of gases is higher than liquids which is turn is higher than solid.

Here, NO2 is a gas with higher complex structure (trigonal planar) than N2 (linerar), N2O (linear) and N2O2 (linear)

Hence, NO2 (g) will have greatest standard molar entropy

Option A is correct