Gas Laws Fact Sheet

\begin{tabular}{|c|c|}
\hline
Ideal gas law & [tex]$PV = nRT$[/tex] \\
\hline
Ideal gas constant & \begin{tabular}{l}
[tex]$R = 0.0821 \frac{L \cdot atm}{mol \cdot K}$[/tex]
\end{tabular} \\
\hline
Standard atmospheric pressure & [tex]$1 atm = 101.3 kPa$[/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.

Leon uses a pressure gauge to measure the air pressure in one of his car tires. The gauge shows that the pressure is 220 kilopascals. The temperature is 297 K, and the outdoor air is at standard pressure. If the tire contains 4.8 moles of air, what is the volume of the tire?

The volume of the car tire is [tex]$\square$[/tex] liters.



Answer :

Let's use the ideal gas law to find the volume of the tire. The ideal gas law is given by:

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

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

Given values:
- [tex]\( P = 220 \, \text{kPa} \)[/tex]
- [tex]\( T = 297 \, \text{K} \)[/tex]
- [tex]\( n = 4.8 \, \text{moles} \)[/tex]
- [tex]\( R = 8.314 \, \text{J/(mol}\cdot\text{K)} \)[/tex]

First, convert the pressure from kilopascals to pascals since 1 kPa = 1000 Pa:

[tex]\[ P = 220 \, \text{kPa} \times 1000 = 220000 \, \text{Pa} \][/tex]

Now, apply the ideal gas law to solve for [tex]\( V \)[/tex]:

[tex]\[ V = \frac{nRT}{P} = \frac{4.8 \, \text{moles} \times 8.314 \, \text{J/(mol}\cdot\text{K)} \times 297 \, \text{K}}{220000 \, \text{Pa}} \][/tex]

Calculate this step-by-step:

1. Calculate the numerator:

[tex]\[ 4.8 \times 8.314 \times 297 = 11860.4544 \, \text{J} \][/tex]

2. Divide by the pressure:

[tex]\[ \frac{11860.4544 \, \text{J}}{220000 \, \text{Pa}} = 0.05387472727272727 \, \text{m}^3 \][/tex]

Since 1 cubic meter (m[tex]\( ^3 \)[/tex]) equals 1000 liters, convert the volume to liters:

[tex]\[ 0.05387472727272727 \, \text{m}^3 \times 1000 = 53.87472727272727 \, \text{liters} \][/tex]

Rounded to two significant figures, the volume of the car tire is:

[tex]\[ 54 \, \text{liters} \][/tex]

Thus, the volume of the car tire is:

[tex]\[ \boxed{54} \, \text{liters} \][/tex]