Heat Of Fusion Formula and Sample Problems

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.

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