A) How many kJ of heat are necessary to melt the solid H2O? B) How many kJ of he

ID: 484438 • Letter: A

Question

A) How many kJ of heat are necessary to melt the solid H2O?

B) How many kJ of heat are necessary to warm the liquid H2O from 0.00 oC to 100.0 oC?

C) How many kJ of heat are necessary to boil the H2O, once at the boiling point?

D) What is the total amount of heat energy, in kJ, needed to heat a 54.0 gram sample of H2O(s) from 0.0 oC until it has completely boiled?

For water 6.01 kJ/mol Enthalpy of Fusion, AH TuS Heat Capacity of Liquid, 18 J/g oc Cs(liquid) Enthalpy of Vaporization, AHvap 40.7 kJ/mol

Given

54 g sample of water

Molar mass of water = 18 g/mol

Moles of water = 54 g /18 g/mol = 3 moles of water

Given :

Enthalpy of fusion of water = 6.01 KJ/mol

heat capacity of liquid = 4.18 KJ/g oC

Enthalpy of Vaporization = 40.7 KJ/mol

Solution:

(a) Energy required to melt given sample = 6.01 KJ/mol * 3 mol = 18.03 KJ

Answer : 18.03 KJ

(b) Heat required to warm 54 g of liquid from 0 C ( 273 K) to 100 C ( 373 K) = 54 g *(100-0) C * 4.18 J/g C

Answer: 22572 J = 22.572 KJ

Answer : 120.21 KJ

(d) Total amount of energy to ris e from 0 c to until it is completely boil = 18.03 + 22.572 + 120.21 = 160.812 KJ

Answer: 160.812 KJ

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.