Properties Of Solids And Liquids Question 118
Question: 10 gm of ice at - 20°C is dropped into a calorimeter containing 10 gm of water at 10°C; the specific heat of water is twice that of ice. When equilibrium is reached, the calorimeter will contain
Options:
A) 20 gm of water
B) 20 gm of ice
C) 10 gm ice and 10 gm water
D) 5 gm ice and 15 gm water
Show Answer
Answer:
Correct Answer: C
Solution:
Heat given by water $ Q _{1}=10\times 10=100cal. $
Heat taken by ice to melt Q2 = 10 ´ 0.5 ´ [0 - (- 20)] + 10 ´ 80 = 900 cal .
As $ Q _{1}<Q _{2}, $ so ice will not completely melt and final temperature = 0°C.
As heat given by water in cooling up to 0°C is only just sufficient to increase the temperature of ice from - 20°C to 0°C, hence mixture in equilibrium will consist of 10 gm ice and 10 gm water at 0°C.
