Q.
Ice at $-20^{\circ} C$ os added tp $50\, g$ of water at $40^{\circ}C$. When the temperature of the mixture reaches $0^{\circ}C$, it is found that $20\, g$ of ice is still unmelted. The amount of ice added to the water was close to
(Specific heat of water = $4.2 \; J/g/^{\circ}C$)
Specific heat of Ice = $2.1 \; J/g/^{\circ}C$
Heat of fusion of water at $0^{\circ}C = 334 \; J/g$)
Solution: