Question

How much heat in calories is required for (2.7 lb) of ice –200 F to be converted to water at 40 F?

Answer 1

Convert -200 F to C
Convert 40 F to C.
Convert 2.7 lb ice to grams ice.

q1 = heat needed to raise T from -200 F (in C of course) to zero C
q1 = mass ice x specific heat ice x (Tfinal-Tinitial)

q2 = heat needed to change phase of ice from solid at zero C to liquid at zero C; i.e., to melt ice at zero C.
q2 = mass ice x heat fusion

q3 = heat needed to raise T of ice from zero to 40 F (in C of course)
q3 = mass H2O x specific heat liquid water x (Tfinal-Tinitial)

Total heat needed = q1 + q2 + q3.