The number of grams of ice that can be melted by 1 g of 100°C steam is
A)0.125 g.
B)0.148 g.
C)6.75 g.
D)8 g.
E)none of the above

Question

Quizplus · Accepted Answer

When 1 g of steam at 100°C condenses to water at 100°C, it releases 540 calories (latent heat of vaporization). This energy can melt ice, which requires 80 calories per gram (latent heat of fusion). Therefore, 540 calories can melt 540/80 = 6.75 g of ice. However, the steam also cools from 100°C to 0°C, releasing an additional 100 calories (1 g x 1 cal/g°C x 100°C), totaling 640 calories. Thus, 640/80 = 8 g of ice can be melted.

The Number of Grams of Ice That Can Be Melted