Question

Which of the following is not a state function?
(A)- Temperature
(B)- Density
(C)- Work
(D)- Volume
(E)- Pressure.

Answer 1

Hint: The quantity or unit which is used to describe the path of any substance or depends on the obtained mechanism of that substance is not considered as a state function, instead of it that will be considered as a path function.

Complete step by step answer:
From the definition, it is clear that those which depend on the mechanism or path are considered as a path function. Now we will discuss the above-given options whether they belong from the state function or from the path function.
-Temperature describes a particular state of any substance and doesn’t depend on the formation mechanism of that substance. If temperature changes then the state of the given substance is also changed, so we conclude that it is a state function.
-Density is also a state function because each and every substance has different density values at different states.
-Work depends on the route or path of the action or mechanism of formation of any substance, so we will consider work as a path function, not a state function.
-Volume is also a state function as all parameters change on going from one state to another state.
-Similarly, the pressure is also a state function as it does also not depend on the path of formation and describes only a particular state of any substance.
From the above discussion, it is clear that work is a path function, not a state function
So, the correct answer is “Option C”.

Note: Here some of you may think that when we change temperature, pressure, density, and volume of any substance their state is also getting changed, so it will also not be a state function. But that assumption is wrong because after getting a changed state value of temperature, pressure, density & volume is also getting changed for that particular state.