Question

Propane (C3H3) is used in domestic cooking and heating. A typical home in Pennsylvania burns 750 gal of propane for heating over the course of a year. How many moles of propane are burned? (the density of propane is approximately 4.2lb/gal)

Answer 1

Answer: There are 32400 moles of propane burned.

Explanation:

To calculate the mass of propane, we use the equation:

$\text{Density of substance}=\frac{\text{Mass of substance}}{\text{Volume of substance}}$

Density of propane = $4.2lb/gal$

Volume of propane = 750 gal

Putting values in above equation, we get:

$4.2lb/gal=\frac{\text{Mass of propane}}{750gal}\\\\\text{Mass of propane}=(4.2lb/gal\times 750gal)=3150lb=1428840g$     (1 lb=453.6 g[/tex]

According to avogadro's law, 1 mole of every substance weighs equal to molecular mass and contains avogadro's number $6.023\times 10^{23}$ of particles.

To calculate the moles, we use the equation:

$\text{Number of moles}=\frac{\text{Given mass}}{\text {Molar mass}}=\frac{1428840g}{44.1g/mol}=32400moles$

Thus there are 32400 moles of propane burned.