Question

$100g$ of ice (latent heat $80cal{g}^{-1}$,at $0^{o}C$) is mixed with $100g$ of water (specific heat 1 cal $g^{-1}a{t}^o{C}^{-1}$) at ${80}^{o}C$. The final temperature of the mixture will be:

• A. $0^{o}C$
• B. ${40}^{o}C$
• C. ${80}^{o}C$
• D. $<0^{o}C$

Answer 1

The correct option is A $0^{o}C$

let all ice melts and goes to $100\times 80+100\times 1(0-0)\Rightarrow 100\times 1(80-\theta )$
$8000+100\theta \Rightarrow 8000-100\theta$
$200\theta \to 0$
$\theta =\to 0^o$