Directions : In the following question more than one of the answers given may be correct. Select the correct answer and mark it according to the code:
During the melting of a slab of ice at 273 K at atmospheric pressure (1) pressure work is done by the ice-water system on the atmosphere (2) positive work is done on the ice-water system by the atmosphere (3) the internal energy of the ice-water system decreases (4) the internal energy of the ice-water increasesA) 1, 2 and 3 are correct
B) 1 and 2 are correct
C) 2 and 4 are correct
D) 1 and 3 are correct
Correct Answer: C
Solution :
There is a decreases in volume during melting on an ice slab at 273 K. Therefore, negative work is done by ice-water system on the atmosphere or positive work is done on the ice-water system by the atmosphere. Hence, option is correct. Secondly heat is absorbed during melting (i.e., dQ is positive) and as we have seen, work done by ice-water system is negative (dW is negative). Therefore, from first law of thermodynamics \[dU=dQ-dW\] Change in internal energy of ice-water system, dU will be positive or internal energy will increase.
You need to login to perform this action.
You will be redirected in
3 sec
