Avogadro’s Law Calculator

This Avogadro’s law calculator helps you explore the relationship between the volume and the amount of a gas. Learning Avogadro’s principle will help you solve various gas law problems and understand how gases behave under different conditions.

We will explain the equation behind this Avogadro’s law calculator as well as discuss an example of how to apply Avogadro’s law to a real-life problem. Let’s begin with the definition of Avogadro’s gas law.

Avogadro’s gas law says that the volume occupied by a gas is directly proportional to the number of moles of gas, provided that the temperature and pressure remain constant.

For example, if you double the amount of gas (while keeping the temperature and pressure constant), Avogadro’s principle says that the volume will also double.

Symbolically, Avogadro’s principle can be expressed as:

$V∝n$

where $V$ is the volume of the gas and $n$ is the amount of gas in moles.

In other words, the ratio of volume to the number of moles is constant:

$V / n = k$

where $k$ is the constant of proportionality.

Avogadro’s law can also be stated as follows:

Equal volumes of gases at the same temperature and pressure contain the same number of molecules.

A balloon contains 3 moles of gas and has a volume of 6 liters. If the amount of gas increases to 5 moles while the temperature and pressure stay constant, what is the new volume?

For two different states of the same gas, Avogadro’s law equation can be written as:

$V_1/n_1 = V_2/n_2$ ​

where:

• $V_1$ is the initial volume of the gas;
• $n_1$ is the initial amount of gas in moles;
• $V_2$ is the final volume of the gas; and
• $n_2$ is the final amount of gas in moles.

For our problem, we have

• $V_1 = 6 \text{ liters}$;
• $n_1 = 3 \text{ moles}$;
• $V_2 = \text{ ?}$; and
• $n_2 = 5 \text{ moles}.$

Using Avogadro’s law formula, we obtain:

$V_2 = n_2/n_1 × V_1$

Plugging in our values yields the answer: ​

$V_2 = 5/3 × 6 = 10 \text{ liters}$ ​

To use this Avogadro’s law calculator, follow these steps:

1. The calculator has four fields, corresponding to the variables in Avogadro’s law equation explained above.
2. Enter the volumes and amounts of gas which you know.
3. Leave empty the field corresponding to the unknown value.
4. The calculator will apply Avogadro’s law formula to find the missing quantity. That’s it!