• # question_answer )  5g ice at $0{}^\circ C$ is mixed with 5g of steam at $100{}^\circ C$ What is the final temperature? A)  $50{}^\circ C$                       B)  $100{}^\circ C$  C)  $80{}^\circ C$               D)         $150{}^\circ C$

Heat required by ice to raise its temperature to $100{}^\circ C,$ \begin{align} & {{Q}_{1}}={{m}_{1}}{{L}_{1}}+{{m}_{1}}{{c}_{1}}{{\theta }_{1}}=5\times 80+5\times 1\times 100 \\ & =400+500=900cal \\ \end{align} Heat given by steam when condensed, \begin{align} & {{Q}_{2}}={{m}_{2}}{{L}_{2}}=5\times 536=2680cal \\ & {{Q}_{2}}>{{Q}_{1}} \\ \end{align} This means that whole steam is not even condensed. Hence temperature of mixture will remain at $100{}^\circ C$.