Question

Extensive properties depend on the quantity of matter but intensive properties do not. Explain whether the following properties are extensive or intensive.
Mass, internal energy, pressure, heat capacity, molar heat capacity, density, mole fraction, specific heat, temperature and molarity.

Answer 1

Hint :The properties whose value depends on the size or the quantity of matter present in the system are called extensive properties. The properties whose value does not depend on the size or the quantity of matter present in the system are called intensive properties.

Complete Step By Step Answer:
Remember that the ratio of two extensive properties is always an intensive property. The mass of a substance depends on the amount of substance. So, it is an extensive property. The magnitude of internal energy depends on the amount of substance in a given state, so it is an extensive property. Pressure is an intensive property. Heat capacity depends on the size and mass of the sample, so it is an extensive property. Molar heat capacity does not depend on the size and mass of the sample, so it is an intensive property. Density is an intensive property because it is the ratio of two extensive properties mass and volume. Mole fraction and molarity are intensive properties because they are the same whether we take a small amount of the solution or a large amount of the solution. Specific heat is an intensive property. The temperature is an intensive property as it does not depend on size and mass.

Note :
Pressure is the ratio of force by area. Force is the product of mass and acceleration and the mass of a body is an extensive property as it depends on the number of particles. The product of an intensive property and an extensive property is extensive. The area is also an extensive property. The ratio of two extensive properties will be an intensive property. So, pressure is an intensive property.