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when you go out to your car one cold winter morning you discover a 0.80 cm thick layer of ice on the windshield which has an area of 1.4m square if the temperature of the ice is - 2.0 degrees celsius and its density is 917 kg/m to the third find the heat required to melt all the ice

User Keith Bentrup
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1 Answer

20 votes
20 votes

Answer:

The total heat required to melt the ice is approximately 3.473 MJ

Step-by-step explanation:

The given parameters for the layer of ice are;

The thickness of the layer of ice, t = 0.80 cm = 0.008 m

The area of the wind shield, A = 1.4 m²

The initial temperature of the ice, T₁ = -2.0 °C = 271.15 K

The density of the ice, ρ = 917 kg/m

The temperature at which ice melts, T₂ = 0 °C = 273.15 K

We have;

The mass of the ice, m = ρ × t × A

∴ m = 917 kg/m³ × 0.008 m × 1.4 m² = 10.2704 kg

The specific heat capacity of ice, c = 2,090 J/(kg·K)

∴ The equation for the heat capacity of the ice to melt, is given as follows;

ΔQ = m·c·ΔT

Where;

ΔT = T₂ - T₁

∴ ΔT = T₂ - T₁ = 273.15 K - 271.15 K = 2 K

ΔQ = 10.2704 kg × 2,090 J/(kg·K) × 2 K = 42.930272 kJ

The latent heat to melt the ice, Q = The latent heat of fusion of ice, L × Mass of ice, m

The latent heat of fusion of ice, L = 334 kJ/kg

∴ Q = 334 kJ/kg × 10.2704 kg = 3,430.3136 kJ

The total heat required to melt the ice, H = ΔQ + Q

∴ H = 42.930272 kJ + 3,430.3136 kJ = 3,473.243872 kJ ≈ 3.473 MJ.

User Wavetree
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