Answer:
The mass methane (CH4) required is, 25 grams (option C)
Explanation:
Mass of oxygen gas = 100 g
Molar mass of oxygen gas = 32 g/mole
Molar mass of methane gas = 16 g/mole
Step 1: Balance the reaction
2O2 + CH4 → CO2 + 2H2O
Step 2: Calculate the moles of O2:
Moles O2 = mass of O2 / Molar mass of o2
Moles O2 = 100g / (32g/mole) = 3,125 moles
⇒From the balanced reaction we conclude that 2 moles of O2 react with 1 mole of CH4
⇒ So, 3.125 moles of O2 react with 3.125/2 = 1.563 moles of CH4
Step 3: Calculate the mass of CH4:
Mass of CH4 = moles of CH4 x Molar mass of CH4
Mass of CH4 = 1.563 moles / (16g/ moles) = 25.008 grams CH4