Answers to Practice Questions

1. Aluminium has a specific heat capacity of 900J/kg°C. Calculate the amount of energy needed to raise the temperature of a 2.5kg aluminium block from 20°C to 65°C. 

ΔE = m x c x Δθ

Δθ = 65-20 = 45°C

ΔE = 2.5 x 900 x 45

ΔE = 101250J

2. Gold has a specific heat capacity of 130J/kg°C. Calculate the amount of energy needed to raise to the temperature of a 10g gold ring from 20°C to 600°C. 

ΔE = m x c x Δθ

Convert 10g into kg, so 10g = 0.01kg

Δθ = 600-20 = 580°C

ΔE = 0.01 x 130 x 580

ΔE = 754 J

3. 10kJ of energy is transferred 1.5kg of material Y to raise its temperature by 20°C. Calculate the value of the specific heat capacity of Y. 

ΔE = m x c x Δθ

10kJ = 10,000J

Rearrange equation to make c the subject.