In van der Waal's equation of state for a nonideal gas, the term that accounts for intermolecular forces is

In the van der Waals equation of state for a non-ideal gas, the term that accounts for the intermolecular forces is -an^2/V^2.

Here's a step-by-step explanation:

1. The van der Waals equation is an equation of state that extends the ideal gas law to include two corrections. One for intermolecular forces and another for the finite size of gas particles. It is expressed as:

   [P + a(n/V)^2] * [V - nb] = nRT

   where: P is the pressure of the gas, V is the volume of the gas, n is the number of moles of the gas, R is the ideal gas constant, T is the temperature of the gas, a and b are van der Waals constants.

2. The term a(n/V)^2 is the correction for intermolecular forces. This term is subtracted from the pressure P because the attractive forces between molecules effectively reduce the pressure of the gas.

3. The constant 'a' is a measure of the strength of the intermolecular forces. The larger the value of 'a', the stronger the intermolecular forces.

4. The term 'n/V' is the number of moles per volume, or the density of the gas. Squaring this term and multiplying by 'a' gives the correction for intermolecular forces.

5. Therefore, the term -a(n/V)^2 in the van der Waals equation accounts for the intermolecular forces in a non-ideal gas.