Question

What mass of carbon dioxide is produced from the complete combustion of 6.30×10−3 g of methane? Express your answer with the appropriate units.

Answer 1

Ans. Balanced equation:      CH₄(g) + 2 O₂(g) --------> CO₂(g) + 2 H₂O(g)

# Stoichiometry: 1 mol CH₄ produces 1 mol CO₂.

# Moles of CH₄ combusted = Mass/ Molar mass

                                                = (6.30 x 10^-3) g / (16.04276 g/ mol)

                                                = 3.9270 x 10^-4 mol

# Following stoichiometry of balanced reaction, the moles of CO₂ produced is equal to moles of CH₄ taken.

So,

            Moles of CO₂ produced = 3.9270 x 10^-4 mol = Moles of CH₄

Now,

            Mass of CO₂ produced = Moles x molar mass

                                                = 3.9270 x 10^-4 mol x (44.0098 g/ mol)

                                                = 1.7283 x 10^-2 g

Hence, mass of CO₂ produced = 1.73 x 10^-2 g