$\overline{){\mathbf{PV}}{\mathbf{=}}{\mathbf{nRT}}}$

$\frac{\mathbf{PV}}{\mathbf{RT}}{\mathbf{=}}\frac{\mathbf{n}\overline{)\mathbf{RT}}}{\overline{)\mathbf{RT}}}\phantom{\rule{0ex}{0ex}}\phantom{\rule{0ex}{0ex}}{\mathbf{n}}{\mathbf{=}}\frac{\mathbf{PV}}{\mathbf{RT}}{\mathbf{=}}\frac{(125\overline{)\mathrm{psi}}\times {\displaystyle \frac{1\overline{)\mathrm{atm}}}{14.7\overline{)\mathrm{psi}}}})(860\overline{)\mathrm{mL}}\times {\displaystyle \frac{{10}^{-3}\overline{)L}}{1\overline{)\mathrm{mL}}}})}{(0.08206{\displaystyle \frac{\overline{)L\xb7\mathrm{atm}}}{\mathrm{mol}\xb7\overline{)K}}})(25+273.15)\overline{)\mathbf{K}}}$

**n = 0.299 mol**

Olympic cyclists fill their tires with helium to make them lighter. Assume that the volume of the tire is 860 mL , that it is filled to a total pressure of 125 psi , and that the temperature is 25 ^{o}C. Also, assume an average molar mass for air of 28.8 g/mol.

Calculate the mass of helium in a helium-filled tire.

Frequently Asked Questions

What scientific concept do you need to know in order to solve this problem?

Our tutors have indicated that to solve this problem you will need to apply the The Ideal Gas Law concept. You can view video lessons to learn The Ideal Gas Law. Or if you need more The Ideal Gas Law practice, you can also practice The Ideal Gas Law practice problems.