Question

A beaker contains 40 g of water at ${20}^{\circ }C$. Now 50 g of ice 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 released by water at ${20}^{o}C$ to $0^{o}C$ $=40\times 1\times 20=600cal$

Heat required to melt $50g$ of ice into water $=50\times 80cal=4000cal$

Because required heat is much more than released heat so final temperature is $0^{o}C$.