Gas Laws Fact Sheet

\begin{tabular}{|c|c|}
\hline
Ideal gas law & [tex]$PV = nRT$[/tex] \\
\hline
Ideal gas constant & \begin{tabular}{l}
[tex]$R = 8.314 \frac{\text{J}}{\text{mol} \cdot \text{K}}$[/tex] \\
or \\
[tex]$R = 0.0821 \frac{\text{L} \cdot \text{atm}}{\text{mol} \cdot \text{K}}$[/tex]
\end{tabular} \\
\hline
Standard atmospheric pressure & [tex]$1 \text{atm} = 101.3 \text{kPa}$[/tex] \\
\hline
Celsius to Kelvin conversion & [tex]$K = { }^{\circ}C + 273.15$[/tex] \\
\hline
\end{tabular}

Type the correct answer in the box. Express your answer to two significant figures.

The gas in an engine cylinder is compressed until it has a volume of 0.045 liters and an absolute pressure of 28 atmospheres. If the engine cylinder contains 0.020 moles of gas, what is its temperature?

The temperature of the gas is [tex]$\square \, K$[/tex]



Answer :

To solve for the temperature of the gas in the engine cylinder, we will use the Ideal Gas Law equation:

[tex]\[ PV = nRT \][/tex]

where:
- [tex]\( P \)[/tex] is the pressure,
- [tex]\( V \)[/tex] is the volume,
- [tex]\( n \)[/tex] is the number of moles,
- [tex]\( R \)[/tex] is the ideal gas constant,
- [tex]\( T \)[/tex] is the temperature in Kelvin.

Given values:
- Volume ([tex]\( V \)[/tex]) = 0.045 liters
- Pressure ([tex]\( P \)[/tex]) = 28 atmospheres
- Number of moles ([tex]\( n \)[/tex]) = 0.020 moles
- Ideal gas constant ([tex]\( R \)[/tex]) = 0.0821 [tex]\( \frac{L \cdot atm}{mol \cdot K} \)[/tex]

We need to solve for [tex]\( T \)[/tex]. Rearranging the Ideal Gas Law equation to solve for temperature ([tex]\( T \)[/tex]):

[tex]\[ T = \frac{PV}{nR} \][/tex]

Substitute the known values into the equation:

[tex]\[ T = \frac{(28 \text{ atm})(0.045 \text{ L})}{(0.020 \text{ mol})(0.0821 \frac{L \cdot atm}{mol \cdot K})} \][/tex]

After performing the calculations:

[tex]\[ T = 767.3568818514007 \text{ K} \][/tex]

Expressing the answer to two significant figures, the temperature of the gas is:

[tex]\[ T \approx 770 \text{ K} \][/tex]

So, the temperature of the gas is [tex]\( \boxed{770} \)[/tex] K.