A calorimeter of mass 50 g and specific heat capacity 0.40Jg'°C-contains 200 g of water
at 40°C. What amount of ice at 0°C should be added to it so that the final temperature is
10°C? [specific heat capacity of water = 4.2 Jg !°C- and specific latent heat of fusion of
Te = 336] g-'°C-
Answers
Explanation:
Heat energy given by metal piece =m⋅c⋅ΔT
1
=20×0.3×(100−22)
=468J
Heat energy gained by water =m
w
×c
w
×ΔT
2
=m
w
×4.2×(22−20)
=m
w
×8.4J
Heat energy gained by calorimeter =m
c
×c
c
×ΔT
2
=50×0.42×(22−20)
=42J
By principle of calorimeter:
Heat lost = Heat gained
Heat energy given by metal = Heat energy gained by water + Heat energy gained by calorimeter
468=m
w
×8.4+42
m
w
=
8.4
468−42
=50.7g
Therefore, the mass f water used in the calorimeter is 50.7g.