2. Find the heat required to convert 20 g of ice
at 0 °C into water at the same temperature
Answers
Explanation:
Given: ice of mass 20 Kg at −4
0
C to water at 20
0
C
To find: the amount of heat energy required to convert ice to water
Solution:
As per the given condition,
Latent heat of fusion of ice, L=3.34×10
5
J/Kg.
Specific heat capacity of water, s=4180J/Kg/K
Specific heat of ice, c=2093J/Kg/K
Mass of ice, m=20kg
The total heat required will be sum of heat energy needed to change the temperature of ice from –4°C to 0°C plus heat required to undergo a solid to liquid phase change at its melting point plus heat required to heat the sample from 0
∘
C to 20
∘
C
q
total
=q
1
+q
2
+q
3
⟹q
total
=mc(ΔT)+mL+ms(ΔT)
⟹q
total
=20×2093×(0−(−4))+20×3.34×10
5
+20×4180(20−0)
⟹q
total
=167440+66.8×10
5
+1672000
⟹q
total
=8519440J=8.52×10
3
kJ
is the quantity of heat is required to transform the ice into water