Determine the change in entropy of 1 mol of sodium chloride when heated from 20 to 850 ° C, if it is known that the molar heat capacity of solid sodium chloride is Cp (t) = 45.94 16.32 ∙ 10-3T J / mol ∙ deg and for liquid compound СР (l) = 66.53 J / mol ∙ deg; heat of fusion 31.0 kJ / mol; melting temperature 800 ° C.