How much energy does a freezer need to remove from 1.2 kg of water at 20°C to make ice at -6°C? [Sp

Question

How much energy does a freezer need to remove from 1.2 kg of water at 20°C to make ice at -6°C?

[Specific heat capacity of water = 4200 Jkg⁻¹K⁻¹, Specific heat capacity of ice = 2100 Jkg⁻¹K⁻¹]

[Latent heat of fusion of ice = 334000 Jkg⁻¹]

Answer 1

How much energy does a freezer need to remove from 1.2 kg of water at 20°C to make ice at -6°C?

[Specific heat capacity of water = 4200 Jkg⁻¹K⁻¹, Specific heat capacity of ice = 2100 Jkg⁻¹K⁻¹]

[Latent heat of fusion of ice = 334000 Jkg⁻¹]

Explanation

Cooling water from 20 °C to 0 °C: 1.2 × 4200 × 20 = 100,800 J.

Freezing at 0 °C: 1.2 × 334,000 = 400,800 J.

Cooling ice from 0 °C to −6 °C: 1.2 × 2100 × 6 = 15,120 J.

Total = 516,720 J.

Was this explanation helpful?

Something wrong or missing? Tell us — we read every report and fix issues fast.