Question

An iron ball of mass 50 g is heated to 236 ℃ and then dropped into a 
    calorimeter of mass 80 g containing 60 g of water at 20 ℃. The final 
    temperature of a mixture is 23 ℃. Find the specific heat capacity of the metal.
    Given: Specific heat capacity of copper = 400 J /kg ℃
                 Specific heat capacity of water = 4200 J /kg ℃​

Answer 1

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.