How much heat energy is required to raise the temperature of 5 kilograms of coal from 20°C to 220°C?

a. 1,314,718 J

b. 314 J

c. 4,187,000 J

d. 6,573 J

Given:

5 kg of coal

T1 = 20°C, T2 = 220°C

Required:

Q (heat energy)

Solution:

The specific heat of coal (bituminous) is 1.315 kJ/kg-K

Q = mcp (T2-T1)

Q = 5kg (1.315 kJ/kg-K) (220 - 20)

Note that T (°C) = T (K)

Q = 1315 kJ or 1315000 J

Since 1315000 J is close to 1314718 J, the answer is letter A.