Gas Laws Fact Sheet

\[

\begin{array}{|l|l|}

\hline

\text{Ideal gas law} & PV = nRT \\

\hline

\text{Ideal gas constant} & \begin{array}{l}

R = 8.314 \, \frac{L \cdot \text{kPa}}{\text{mol} \cdot K} \\

\text{or} \\

R = 0.0821 \, \frac{L \cdot \text{atm}}{\text{mol} \cdot K}

\end{array} \\

\hline

\text{Standard atmospheric pressure} & 1 \, \text{atm} = 101.3 \, \text{kPa} \\

\hline

\text{Celsius to Kelvin conversion} & K = ^\circ C + 273.15 \\

\hline

\end{array}

\]

Select the correct answer.

The gas in a sealed container has an absolute pressure of 125.4 kilopascals. If the air around the container is at a pressure of 99.8 kilopascals, what is the gauge pressure inside the container?

A. 1.5 kPa

B. 24.1 kPa

C. 25.6 kPa

D. 1126 kPa

E. 225.2 kPa

To determine the gauge pressure inside the container, we use the following relation:

$$
\text{Gauge Pressure} = \text{Absolute Pressure} - \text{Atmospheric Pressure}
$$

The absolute pressure is given as $125.4\,\text{kPa}$ and the atmospheric pressure is $99.8\,\text{kPa}$. Substituting these values, we have:

$$
\text{Gauge Pressure} = 125.4\,\text{kPa} - 99.8\,\text{kPa} = 25.6\,\text{kPa}
$$

Thus, the gauge pressure inside the container is $25.6\,\text{kPa}$.

The correct answer is:

C. $25.6\,\text{kPa}$