Answer to Question #265129 in General Chemistry for franz

Question

What is the mass in grams of oxygen gas, O2 is needed to complete the combustion of 6 L of methane, CH4? Assume that the pressure and temperature remain constant. (be sure to write the balanced chemical equation)

Answer 1

CH₄ + 2O₂ → CO₂ + 2H₂O

One mole of any gas at STP occupy volume of 22.4 L.

Proportion:

22.4 L – 1 mol

6 L – x

$x = \frac{6 \times 1}{22.4} = 0.2678 \;mol$

According to the reaction:

n(O₂) = 2n(CH₄) $= 2 \times 0.2678 = 0.5356 \;mol$

M(O₂) = 32 g/mol

m(O₂) $= 0.5356 \times 32 = 17.14 \;g$

Answer: 17.14 g