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How much heat is required to change 200 mL of ice at -22°C (at typical Freezer temperature) into steam

User Claptimes
by
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1 Answer

2 votes

Answer:

611.064 kJ

Step-by-step explanation:

Given :

m = 200 mL = 200 g

Specific heat of ice = 2.06 J/g°C

Q = mcΔt

Δt = 0 - (-22) = 22

Q1 = 200 * 2.06 * 22 = 9064 J

Q2 = Melt 0 °C solid ice into 0 °C liquid water:

Q2 = m · ΔHf ; ΔHf = heat of fusion of water = 334j/g

Q2 = 200 * 334 = 66800 J

Q3 : Heat to convert from 0°C to 100°C

Q3 = mcΔt ; c = 4.19 J/g°C ; Δt = (100 - 0) = 100

Q3 = 200 * 4.19 * 100 = 83800 J

Q4: heat required to boil water to steam

Q = m · ΔHv

Hv = heat of vaporization of water = 2257 J/g

Q4 = 200 * 2257 = 451400 J

Total Q = Q1 + Q2 + Q3 + Q4

Q = 9064 + 66800 + 83800 + 451400

Q = 611,064 Joules

Q = 611.064 kJ

User Mehrdad Shokri
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