# A balloon has a volume of 20.0 L at atmospheric pressure and 20.0 C. One wants to increase the volume to 24.0 L at constant pressure. To what temperature in degrees Celsius does one need to increase the temperature to?

##### 1 Answer

The answer is 79 °C.

#### Explanation:

As the initial volume of 20 L is less than the final volume of 24 L, the temperature must increase.

This is based on Charles' Law, which states that there is a direct relationship between temperature and volume.

If your answer is less than 20 L, the answer is wrong.

It is important to remember that Charles' Law is based on Kelvin temperatures.

**Step one** is to change Celsius degrees into kelvins.

∴

**Step two** is to insert the values into the Charles' Law expression.

**Step three** is to convert the Kelvin temperature to Celsius.

To change this answer back to Celsius degrees, subtract 273.