Question

In thermodynamics, heat and work are:

• A. Intensive thermodynamics states variables
• B. Extensive thermodynamics state variables
• C. Path functions
• D. Point functions

Answer 1

The correct option is C

Path functions

The explanation of the correct option:

Correct option is C:

1. Both heat and work depend on the path followed during the process.
2. So, heat and work are path functions.
3. Heat and work are independent of their physical properties.
4. So, both are not considered as the case of intensive or extensive properties.

The explanation of the incorrect options:

Option B:

1. An extensive property of a system depends on the system size or the amount of matter in the system.
2. If the value of the property of a system is equal to the sum of the values for the parts of the system then such a property is called extensive property.
3. Volume, energy, and mass are examples of extensive properties

Option A:

1. The properties of matter that do not depend on the size or quantity of matter in any way are referred to as an intensive property of matter.
2. Temperatures, density, colour, melting and boiling point, etc., all are intensive properties as they will not change with a change in size or quantity of matter.
3. The density of 1 litre of water or 100 litres of water will remain the same as it is an intensive property.

Option D:

1. A property whose value doesn’t depend on the path taken to reach that specific value is known to as state functions or point functions.
2. In contrast, those functions which do depend on the path from two points are known as path functions.
3. State functions are the values which depend on the state of the substance like temperature, pressure or the amount or type of the substance. as a matter of fact, state functions do not depend on how the state was reached or established.

Thus, the correct option is c.