How much heat is required in order to change 5 g of ice at -15 degree to steam at 150 degree?

Answer 1

Look up the specific heats of ice, water and steam. Call them Ci, Cw and Cs.

Cw is 1.00 cal/g C

You will also need the heat of fusion
Hf = 80 cal/g
and the heat of vaporization
Hv = 540 cal/g

Q required = 5g * [15Ci + 100Cw + 50 Cs + Hf + Hv] calories