Which of the following is not an intensive property?

Question

Accepted Answer

Internal energy is not an intensive property, and here's why:

1. **Internal Energy (Option 1):** Internal energy is an extensive property, meaning it depends on the amount of substance present. Extensive properties are additive for independent, non-interacting subsystems. For example, if you have two separate systems, each with a certain internal energy, the total internal energy is the sum of the internal energies of the two systems. This characteristic makes internal energy dependent on the size or extent of the system, which is why it is not an intensive property.

2. **Density (Option 2):** Density is an intensive property because it does not depend on the amount of substance present. It is defined as mass per unit volume. Whether you have a small sample or a large sample of a substance, the density remains the same. This constancy across different sample sizes is a hallmark of intensive properties.

3. **Temperature (Option 3):** Temperature is also an intensive property. It is a measure of the average kinetic energy of the particles in a substance and does not change with the size of the system. For instance, the temperature of a cup of water is the same as the temperature of a liter of water, assuming they are in thermal equilibrium.

4. **Pressure (Option 4):** Pressure is an intensive property as well. It is defined as force per unit area and remains constant regardless of the system's size. For example, the pressure exerted by a gas in a container is the same whether the container is large or small, provided the conditions are the same.

In summary, internal energy is the correct answer as it is an extensive property, unlike density, temperature, and pressure, which are intensive properties.