Energy Changes

Calculate the total quantity of heat evolved when 10.0g of steam at 200 C is condensed, cooled , and frozen to ice at 50 C. The specific heat capacity of ice and steam are 2.06J/gC and 2.03J/gC respectively. 1 2 3 4 5 .1 Q = msT Q = (10.0g)(2.03J/gC)(100C) Q = 2030J = 2.030kJ 1 2 n(H2O) = mass / molar mass = 10.0g / 18g mol-1 = 0.56 mol H2O vap H (H2O) = 40.6kJ/mol vap H (H2O) = 0.56 mol  40.6 kJ/mol = 22.7 kJ 2 3 Q = msT Q= (10.0g)(4.18J/gC)(100C) Q = 4180J = 4.180kJ 3 4 n(H2O) = mass / molar mass = 10.0g / 18g mol-1 = 0.56 mol H2O fus H (H2O) = 40.6kJ/mol fus H (H2O) = 0.56 mol  40.6 kJ/mol = 22.74 kJ 4 5 Q = msT Q = (10.0g)(2.06J/gC)(50C) Q = 1030J = 1.030kJ 5 Calculate the total quantity of heat evolved when 10.0g of steam at 200 C is condensed, cooled , and frozen to ice at 50 C. Total heat = 2.030kJ + 22.7 kJ + 4.180kJ + 22.74 kJ + 1.030kJ = 52.68kJ