Question

104g of water at 30°C is taken in a calorimeter made of copper of mass 42 g. When a certain mass of ice at 0°C is added to it, the final steady temperature of the mixture after the ice has melted, was found to be 10°C. Find the mass of ice added. [Specific heat capacity of water = 4.2 Jg^–1°C^–1 ; Specific latent heat of fusion of ice = 336 J^g–1; Specific heat capacity of copper = 0.4 Jg^–1°C^–1] .

Answer 1

m_w =104g 
T_w = 30° C
m_c = 42 g

T =10°C
 m_i = ? 
By Calorimetry,
Heat lost = Heat gained

m_w S_w(T_w -T) + m_c S_c(T_w - T) =m_i α + m_i S_w(T-T_i)   

⇒ (104)(4.2)(30 -10) +(42)(0.4)(30 -10) = m_i (336)+ m_i(4.2)(10- 0)  

⇒ m_i `=((104)(4.2)(20)+(42)(0.4)(20))/((336+42)) = 24 g`