Question

What will be the mass of 9.95 liters of propane gas (C3H8) at STP?

Answer 1

Answer:

19.5g

Explanation:

Given parameters:

Volume of propane gas = 9.95L

Unknown:

Mass of propane gas =  ?

Solution:

To solve this problem, find the number of moles first.

    At STP;

        22.4L of gas makes up 1 mole

         9.95L of gas will have a $\frac{9.95}{22.4}$    = 0.44mole

So;

   Mass of propane gas  = number of moles x molar mass

Molar mass of propane  = 3(12) + 8(1)  = 44g/mol

    Mass  = 0.44 x 44  = 19.5g