1) List the known and unknown quantities.
Sample: Carbon dioxide (CO2)
Mass: 10 g
STP means standard temperature and pressure.
Temperature: 273.15 K.
Pressure: 100000 Pa = 0.986923 atm
Ideal gas constant: 0.082057 L * atm * K^(-1) * mol^(-1)
2) Set the equation.
[tex]PV=nRT[/tex]2.1- Convert g of CO2 to moles of CO2.
The molar mass of CO2 is 44.0095 g/mol.
[tex]mol\text{ }CO_2=10\text{ }g\ast\frac{1\text{ }mol\text{ }CO_2}{44.0095\text{ }g\text{ }CO_2}[/tex][tex]mol\text{ }CO_2=0.2272[/tex]3) Plug in the known quantities in the ideal gas equation and solve for V (liters).
[tex](0.986923\text{ }Atm)(V)=(0.2272\text{ }mol\text{ }CO_2)(0.082057\text{ }L\ast atm\ast K^{-1}\ast mol^{-1})(273.15\text{ }K)[/tex][tex]V=\frac{(0.2272molCO_2)(0.082057\text{ }L\ast atm\ast K^{-1}mol^{-1})(273.15K)}{0.986923\text{ }atm}[/tex][tex]V=5.15991\text{ }L[/tex]10g CO2 would occupy 5.2 L.
Volume: 5.2 L.
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