L. How many grams of H2O and CO2 can be made from 64 g of CH4 and excess O2? 1. H2O 2. CO2?

1.
Molar mass of CH₄ = (12 + 1×4) g/mol = 16 g/mol
Molar mass of H₂O = (1×2 + 16) g/mol = 18 g/mol
Molar mass of CO₂ = (12 + 16×2) g/mol = 44 g/mol

Balanced equation for the reaction:
CH₄ + 2O₂ → CO₂ + 2H₂O
Mole ratio CH₄ : H₂O = 1 : 2

No. of moles of CH₄ reacted = (64 g) / (16 g/mol) = 4 mol
No. of moles of H₂O made = (4 mol) × (2/1) = 8 mol
Mass of H₂O made = (8 mol) × (18 g/mol) = 144 g

2.
Mole ratio CH₄ : CO₂ = 1 : 1
No. of moles of CO₂ made = (4 mol) × (1/1) = 4 mol
Mass of CO₂ made = (4 mol) × (44 g/mol) = 176 g

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Method 2:

1.
(64 g CH₄) × (1 mol CH₄ / 16 g CH₄) × (2 mol H₂O / 1 mol CH₄) × (18 g H₂O / 1 mol H₂O)
= 144 g H₂O

2.
(64 g CH₄) × (1 mol CH₄ / 16 g CH₄) × (1 mol CO₂ / 1 mol CH₄) × (44 g CO₂ / 1 mol CO₂)
= 176 g CO₂