## Heat Of Fusion Formula :

Heat energy q _{(J) } in Joule is the equal to the product of the mass m_{(kg) }in kilogram is multiply by the heat of fusion ΔHf_{(J/k) }in joule per kelvin. Hence the heat of futon formula has been written as,

**q _{(J) }= m_{(kg)} ·ΔHf_{(J/k)}**

Where,

q → heat energy in (Joule).

m → mass in (kg ).

ΔHf → heat of fusion in (J/g).

## Sample Problems :

### Example 1:

Calculate the heat in Joules required to melt 36 grams of ice? Given that heat of fusion of water = 344 J/g = 85 cal/g.

### Solution :

Given parameters are

Mass, m = 36g

We know that

q = m·ΔHf

q = (36 g) * (344 J/g)

= 12384 J.

q = m·ΔHf

q = (36 g)*(85 cal/g)

q =3060 cal.

### Example 2:

Calculate the heat in Joules required to melt 45 grams of ice? Given that heat of fusion of water = 444 J/g = 90 cal/g.

### Solution :

Given parameters are

Mass, m = 45g

We know that

q = m·ΔHf

q = (45g) * (444 J/g)

= 19980 J.

q = m·ΔHf

q = (45g)*(90 cal/g)

q =4050 cal.