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


1.
The mathematical expression of the first law of thermodynamics is:
A.
ΔU = q + w
B.
ΔU = −q + w
C.
ΔU = q − w
D.
ΔU = w − q
😑 View Answer Rough Work Error
ANSWER :
A. ΔU = q + w
2.
The first law of thermodynamics is essentially a statement of:
A.
Conservation of momentum
B.
Conservation of entropy
C.
Conservation of mass
D.
Conservation of energy
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ANSWER :
D. Conservation of energy
3.
For an isolated system, the change in internal energy is:
A.
Equal to the work done
B.
Always positive
C.
Always negative
D.
Zero
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ANSWER :
D. Zero
4.
Internal energy of a system includes:
A.
Only chemical energy
B.
Only potential energy of molecules
C.
Sum of all forms of energy (kinetic, potential, chemical, etc.)
D.
Only kinetic energy of molecules
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ANSWER :
C. Sum of all forms of energy (kinetic, potential, chemical, etc.)
5.
Which of the following is true about internal energy U?
A.
It depends on rate of process
B.
It is a state function and only ΔU can be measured
C.
It is a path function
D.
Its absolute value can be measured
😑 View Answer Rough Work Error
ANSWER :
B. It is a state function and only ΔU can be measured
6.
When 100 J of heat is absorbed by a system and 30 J of work is done on it, ΔU is:
A.
−130 J
B.
+70 J
C.
+130 J
D.
−70 J
😑 View Answer Rough Work Error
ANSWER :
C. +130 J