# Problem: 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 oC. Also, assume an average molar mass for air of 28.8 g/mol.Calculate the mass of helium in a helium-filled tire.

###### FREE Expert Solution

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

n = 0.299 mol

###### Problem Details

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 oC. Also, assume an average molar mass for air of 28.8 g/mol.

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