Enter the volume of the gas and the number of moles of the gas into the Calculator. The calculator will evaluate the Proportionality Constant. 

Proportionality Constant Formula

k = V/n


  • k is the Proportionality Constant ()
  • V is the volume of the gas
  • n is the number of moles of the gas

To calculate the Proportionality Constant, divide the volume of gas by the number of moles of the gas.

How to Calculate Proportionality Constant?

The following steps outline how to calculate the Proportionality Constant.

  1. First, determine the volume of the gas. 
  2. Next, determine the number of moles of the gas. 
  3. Next, gather the formula from above = k = V/n.
  4. Finally, calculate the Proportionality Constant.
  5. After inserting the variables and calculating the result, check your answer with the calculator above.

Example Problem : 

Use the following variables as an example problem to test your knowledge.

the volume of the gas = 111

number of moles of the gas = 3.3

Frequently Asked Questions

What is the Ideal Gas Law and how does it relate to the Proportionality Constant?

The Ideal Gas Law is a fundamental equation in chemistry and physics that describes the behavior of an ideal gas. It is represented as PV=nRT, where P is pressure, V is volume, n is the number of moles, R is the ideal gas constant, and T is temperature. The Proportionality Constant (k) is related to this law as it is derived from the volume (V) of the gas and the number of moles (n) of the gas, which are both components of the Ideal Gas Law.

Can the Proportionality Constant be used for all gases?

The Proportionality Constant, as derived from the formula k = V/n, can be used for ideal gases where the behavior of the gas follows the assumptions of the Ideal Gas Law. However, for real gases under extreme conditions (very high pressure or very low temperature), deviations from ideal behavior are observed, and corrections to the Ideal Gas Law (and hence the Proportionality Constant) may be necessary.

How do temperature and pressure affect the Proportionality Constant?

While the formula for the Proportionality Constant (k = V/n) does not explicitly include temperature and pressure, these factors affect the volume (V) and the number of moles (n) of a gas. Generally, increasing the temperature or decreasing the pressure will increase the volume of a gas, potentially altering the value of the Proportionality Constant for a given amount of substance (n).

Is there a difference between the Proportionality Constant and the Ideal Gas Constant?

Yes, there is a difference. The Proportionality Constant (k) is specific to the volume-to-mole ratio (V/n) for a given sample of gas under specific conditions, making it a variable value dependent on the state of the gas. On the other hand, the Ideal Gas Constant (R) is a universal constant that appears in the Ideal Gas Law (PV=nRT), representing the relationship between pressure, volume, temperature, and the number of moles of an ideal gas, and it remains constant for all ideal gases under any condition.