Question

The chemical equation below shows the combustion of methane (CH4).

CH4 + 2O2 mc031-1.jpg CO2 + 2H2O

The molar mass of oxygen gas (O2) is 32.00 g/mol. The molar mass of carbon dioxide (CO2) is 44.01 g/mol. What mass of CO2, in grams, will form when 8.94 g O2 completely react?
3.25
6.15
13.0
53.0

Answer 1

B

Step-by-step explanation:

edg 2020

Answer 2

The correct answer is 6.15g of CO2 will be produced.

The approach to answer this question is to use the molar mass to find the number of moles of oxygen consumed. Then use the chemical equation to determine the number of moles of CO2 that would be produced (half that of oxygen). Then use the molar mass of CO2 to calculate the mass.

Mmass O2 = 32g/mol
Mmass CO2 = 44.01g/mol
mass O2 consumed = 8.94g
mass CO2 produced = ?

moles O2 = mass / molar mass = 8.94 / 32 = 0.279
moles CO2 = half that of O2 = 0.1397

mass CO2 produced = moles CO2 x molar mass = 0.1397 x 44.01 = 6.15 g

:)