a 100 g sample of ice at -15 degrees celsius is heated until it is converted to water vapour at 120 degrees celsius what is the energy change?

Answer 1

q1 = heat needed to raise T of solid ice from -15 to zero C.
q1 = mass ice x specific heat x (Tfinal-Tinitial)

q2 = heat to melt ice at zero C to liquid H2O at zero C.
q2 = mass ice x heat fusion

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

q4 = heat needed to convert liquid water @ 100 C to vapor at 100 C
q4 = mass H2O x heat vaporization

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

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

Answer 2

Still don't understand this! Please help!