Question

Consider a sample of 20g of water at -20*C and 1.0 atm. Determine the amount of energy required to raise the temperature of this water to 120*C. (Sice=2.1 Jg-1C-1; Swater= 4.184Jg-1C-1; Ssteam=1.7Jg-1C-1; ΔHfus 6.01 kJ/mol; ΔHvap=40.7 kJ/mol)

Answer 1

q1 = heat needed to raise T from -20 to zero.
q1 = mass ice x specific heat ice x (Tfinal-Tinitial)

q2 = heat needed to melt ice at zero to liquid water at zero C.
q2 = mass ice x heat fusion

q3 = heat needed to raise T of liquid water at zero C to 100 C.
q3 = mass H2O x specific heat H2O x (Tfinal-Tinitial)

q4 = heat needed to boil H2O at 100 C to steam at 100 C
q4 = mass H2O x heat vaporization

q5 = heat needed to raise T of steam at 100 C to steam at 120 C.
q5 = mass steam x specific heat steam x (Tfinal-Tinitial)_

Total Q = q1+q2+q3+q4+q5