Column I | Column II | ||
a. | No heat is absorbed by the system from the surroundings, but work (w) is done on the system. | i. | ∆U = q – w, closed system. |
b. | No work is done on the system, but q amount of heat is taken out from the system and given to the surroundings. | ii. | ∆U = wad, a wall is adiabatic. |
c. | w amount of work is done by the system and q amount of heat is supplied to the system. | iii. | ∆U = –q, thermally conducting walls. |
1. | a = i; b = ii; c = iii | 2. | a = ii; b = i; c = iii |
3. | a = ii; b = iii; c = i | 4. | a = iii; b = ii; c = i |
Two litres of an ideal gas at a pressure of 10 atm expands isothermally at 25 °C into a vacuum until its total volume is 10 litres. The amount of heat absorbed during expansion is:
1. 80 J
2. -80 J
3. Zero
4. 50 J
Two litres of an ideal gas at a pressure of 10 atm expands isothermally at 25 °C against a constant external pressure of 1 atm until its total volume is 10 litres. The amount of heat absorbed during expansion is-
1. 80 atm L
2. -80 atm L
3. -8 atm L
4. 8 atm L
.
Two litres of 1 mol an ideal gas at a pressure of 10 atm expands isothermally at 25 °C into a vacuum until its total volume is 10 litres. The amount of heat absorbed during expansion is:
(Given: The same expansion, for 1 mol of an ideal gas conducted reversibly.
log 5 = 0.699)
1. 51. 39 atm L
2. 39.36 atm L
3. 37. 34 atm ml
4. 26. 49 atm L