Question

What mass of carbon dioxide gas occupies a volume of 81.3L at 204 kPa and a temperature of 95.0°C?

Answer 1

Answer:

236.9g

Explanation:

Given parameters:

Volume of gas  = 81.3L

Pressure of gas = 204kPa

temperature of gas = 95°C

Unknown:

Mass of carbondioxide gas = ?

Solution:

To solve this problem, the ideal gas law will be well suited. The ideal gas law is a fusion of Boyle's law, Charles's law and Avogadro's law.

Mathematically, it is expressed as;

                    PV = nRT

the unknown here is n which is the number of moles;

P is the pressure, V is the volume, R is the gas constant and T is the temperature.

convert pressure into atm

               101.325KPa  = 1atm

             204 kPa = $\frac{204}{101.325}$   = 2atm

Convert temperature to Kelvin;   95 + 273  = 368K

       2 x 81.3 = n x 0.082 x 368

             n = $\frac{2 x 81.3}{0.082 x 368}$   = 5.38moles

Since the unknown is mass;

 Mass  = number of moles x molar mass

      Molar mass of carbon dioxide  = 12 + 2(16)  = 44g/mol

 Mass  = 5.38 x 44  = 236.9g