Question

Calculate the number of kilojoules to warm 125 g of iron from 23.5°C to 78.0°C.

Answer 1

3065.63 Kj, the specific heat of iron is .45

Answer 2

Answer:

            Q  =  3.06 kJ

Solution:

The equation used for this problem is as follow,

                                                 Q  =  m Cp ΔT   ----- (1)

Where;

           Q  =  Heat  =  ?

           m  =  mass  =  125 g

           Cp  =  Specific Heat Capacity  =  0.450 J.g⁻¹.°C⁻¹

           ΔT  =  Change in Temperature  =  78.0 °C - 23.5 °C  =  54.5 °C

Putting values in eq. 1,

                            Q  =  125 g × 0.450 J.g⁻¹.°C⁻¹ ×  54.5 °C

                            Q  =  3065 J

Or,

                            Q  =  3.06 kJ