A hot water bottle contains 750g of water at 65 C. If the water cools to body temperature (37 C)...?

Question

How many calories of heat could be transferred to sore muscles?
*21000cal

How much heat energy is absorbed when 20.0g of ice melts?
*6680J

Am I right for these 2 questions? I just want to make sure I'm learning this material right. Thanks!

Answer 1

With the calorie unit, heat calculations for water is very simple, because the heat capacity of water is 1 cal / g oC

Use the formula q = m Cp delta T

q = (750 g)(1 cal / g oC)(28 oC)

Just multiply and solve for q.

For the second problem, you need the Heat of Fusion value for ice.

The formula is q = m Hf

I believe Hf for ice is about 338 J / g. So multiply and you are there.