The First Law of Thermodynamics (Concept of Work, Heat Internal Energy and Enthalpy, Heat Capacity,...) NEET Questions

Physical Chemistry - Chemical Thermodynamics

The First Law of Thermodynamics (Concept of Work, Heat Internal Energy and Enthalpy, Heat Capacity,...) MCQ Questions


7.
If a system absorbs 50 J of heat and does 20 J of work on the surroundings, ΔU is:
A.
−70 J
B.
+30 J
C.
+70 J
D.
−30 J
😑 View Answer Rough Work Error
ANSWER :
B. +30 J
8.
A system gives out 25 J of heat and 15 J of work is done on it. The change in internal energy is:
A.
+40 J
B.
−40 J
C.
+10 J
D.
−10 J
😑 View Answer Rough Work Error
ANSWER :
D. −10 J
9.
For a cyclic process, the change in internal energy ΔU is:
A.
Minimum
B.
Zero
C.
Equal to the work done
D.
Maximum
😑 View Answer Rough Work Error
ANSWER :
B. Zero
10.
In an adiabatic process, the first law reduces to:
A.
ΔU = q − w
B.
ΔU = q
C.
ΔU = 0
D.
ΔU = w
😑 View Answer Rough Work Error
ANSWER :
D. ΔU = w
11.
At constant volume, the heat absorbed by a system equals:
A.
ΔH
B.
ΔU
C.
Work done
D.
Zero
😑 View Answer Rough Work Error
ANSWER :
B. ΔU
12.
Internal energy of an ideal gas depends on:
A.
Temperature only
B.
Both pressure and volume
C.
Volume only
D.
Pressure only
😑 View Answer Rough Work Error
ANSWER :
A. Temperature only