How much heat is necessary to melt 56.72 grams of substance Y from solid phase at 15 degrees Celsius to liquid at the same temperature? Melting point of substance Y = 15 degrees Celsius; ΔHvaporization = 2.83 J/mol; ΔHfusion = 5.51 J/mol; MWsubstance y = 14.77 g/mol.Answer 21.2 J 3.13 x 102 J 10.9 J 161 J

Question

How much heat is necessary to melt 56.72 grams of substance Y from solid phase at 15 degrees Celsius to liquid at the same temperature? Melting point of substance Y = 15 degrees Celsius; ΔHvaporization = 2.83 J/mol; ΔHfusion = 5.51 J/mol; MWsubstance y = 14.77 g/mol.Answer 		 21.2 J 		 3.13 x 102 J 		 10.9 J 		 161 J

anonymous · Answer

Convert grams to moles
$$56.72g / 14.77 g/mol= 3.840mol$$
Then simply multiply by the heat of fusion
$$3.840 mol * 5.51J/mol= 21.2J$$