A calorimeter has mass 100 g and
specific heat 0.1 kcal/ kg °C. It
contains 250 gm of liquid at 30 °C
having specific heat of 0.4 kcal/kg
°C. If we drop a piece of ice of mass
10 g at 0 °C, What will be the
temperature of the mixture?
Answers
Answer:
20.83°C
Explanation:
Solution
Let the final temperature attained be T. then,
heat given by calorimeter + heat given by liquid
= heat absorbed by ice
⇒Mc Sc(30−T)+MLSL (30−T)
=Mi[Lfusion+SW(T−0)]
⇒(100)(0.1)(30−T)+(250)(0.4)(30−T)
=10[80+1(T−0)]
⇒(110)(30−T)=10[80+T]
⇒330−11T=80+T
⇒T= 12(330−80)
=20.83° C
Let the final temperature of the mixture be T.
Amount of heat required in converting 10 g ice to 0°C to water at 0°C =
10×80=800 cal
Total amount of heat required in converting 10 g water to 0°C to water at T°C =
10×1×T=10T
Total heat energy required to convert 10 g ice at 0°C to water at T°C = 800 + 10T
Amount of heat released to raise the temperature of calorimeter at 30°C to T°C
100×0.1×(30−T)=10(30−T)
Amount of heat released to raise the temperature of 250g of eater at 30°C to T°C =
250×0.4×(30−T)=100(30−T)
Total amount of heat released in the process =
110(30−T)
Using the principle of calorimetry, we have
110(30−T)= 800 + 10T
⇒T=20.83°C