# If the absolute pressure of a gas is 550.280 kPa, what is its gage pressure?

##### 1 Answer

4.43084 atm

#### Explanation:

The answer is **448.955 kPa**, or **4.43084 atm**.

The difference between **absolute** and **gauge** pressure is determined by their respective zero references.

The zero reference for absolute pressure is set against a perfect vacuum, while the zero reference for gauge pressure is set against ambient pressure.

As a result, absolute pressure is defined as the sum of the gauge pressure and the atmospheric pressure

which makes gauge pressure equal to

Since a value for the atmospheric pressure was not provided, let's assume its **1 atm**, or **101.325 kPa**. This makes the gauge pressure equal to