My approach to this was deltaG= deltaH-TdeltaS. But I couldn't find delta delta f G for liquid N. Is it safe to assume that its zero?

My approach to this was deltaG= deltaH-TdeltaS. But I couldn't find delta delta f G for liquid N. Is it safe to assume that its zero?

Thanks.

Liquid nitrogen freezes to a white solid at −210.00°C, with an enthalpy of fusion of 0.71 kJ/mol. What is its entropy of fusion? Is freezing biological tissue in liquid nitrogen an example of a reversible process or an irreversible process?