A piece of ice of mass 60 g is dropped into 140 g of water

Heat (10)

A piece of ice of mass 60 g is dropped into 140 g of water at 50^o C. Calculate the final temperature of water when all the ice has melted. (Assume no heat is lost to the surrounding)

Specific heat capacity of water = 4.2 Jg^-1k^-1; Specific latent heat of fusion of ice = 336 Jg^-1

Answer

ml + mct = mct

60(336 + 4.2x) = 140 x 4.2 x (50 - x)

60 x 4.2(80 + x) = 140 x 4.2(50 - x)

3(80 + x) = 7(50 - x)

240 + 3x =  350 - 7x

10x = 350 - 240 = 110

x = 11°C