Question

A beaker contains $40g$ of water at ${20}^{\circ }C$. Now $50g$ of ice at $0^{\circ }C$ is put into the beaker. The resulting temperature will be :

• A. $-7^{\circ }C$
• B. $0^{\circ }C$
• C. ${10}^{\circ }C$
• D. ${1.5}^{\circ }C$

Answer 1

The correct option is B $0^{\circ }C$

Heat required for melting of ice to water at $0^{o}C=50\times 80=4000J=4kJ$

Heat released by water at ${20}^{o}C$ to $0^{o}C=40\times 1\times (20-0)=800J$

Released heat is very less than required heat, so final temperature will be $0^{o}C$