Question

Calculate the volume of 100. grams of oxygen gas (O₂) at 25.0°C and a pressure of 1.25 atm.

Answer 1

Ideal gas law states

PV = n(RT)

V is volume (L), P is pressure (atm), R is universal gas constant: 0.0821 L·atm/mol· K, n is number of moles, T is temperature in Kelvin

Here given:

`\blacksquare` mass of O₂ : 100 gram

`\blacksquare` moles: mass/molar mass = 100/32 = 3.125 moles

`\blacksquare` 25.0 °C = (25+273.15) = 298.15 K

`\blacksquare` pressure: 1.25 atm

Volume:

`\boxed{\sf V=(nRT)/(P)}`

`\Rightarrow \sf V=((3.125 \ x \ 0.0821 \ x \ 298.15 ))/(1.25)`

`\Rightarrow \sf V=61.195 \ L`

`\Rightarrow \sf V=61.2 \ L \ \ \ (rounded \ to \ nearest \ tenth)`

Additional Explanation:

• Volume can be counted in multiple units.

In Liters: 61.2 Liters

In cubic meter: 0.061163 m³

In cubic centimeter: 61,163.5 cm³