Q. If there are no heat losses, the heat released by the condensation of $x\ g$ of steam at $100℃$ into water at $100℃$ can be used to convert $y\ gm$ of ice at $0℃$ into water at $100℃.$ Then the ratio $y\ :x$ is nearly
A) $1\ :1$
B) $2.5\ :1$
C) $2\ :1$
D) $3\ :1$
Explanation
(d) Heat released to convert $x\ g$ of steam at $100℃$ to water at $100℃$ is $x \times 540\ cals.$
If $y\ g$ of ice is converted from $0℃$ to water at $100℃$ it requires heat $y \times 80 + y \times 1 \times 100 = 180y$
$\therefore x \times 540 = 180y\ $or $\frac{y}{x} = \frac{540}{180} = \frac{3}{1}$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.