**Problem:**

What is the heat in Joules required to melt 25 grams of ice? What is the heat in calories?

Useful information: heat of fusion of water = 334 J/g = 80 cal/g

**Solution:**

**Part I**

Use the formula

q = m·ΔH

_{f}

where

q = heat energy

m = mass

ΔH

_{f}= heat of fusion

q = (25 g)x(334 J/g)

q = 8350 J

**Part II**

q = m·ΔH

_{f}

q = (25 g)x(80 cal/g)

q = 2000 cal

**Answer:**

The amount of heat required to melt 25 grams of ice is 8350 Joules or 2000 calories.