AP Chemistryeasymcq1 pt
What mass of water is produced by burning 4.0 g of H₂? (H₂ = 2.0, H₂O = 18 g/mol)
A.36 g
B.18 g
C.9.0 g
D.72 g
Explanation
Core Concept
2H₂ + O₂ → 2H₂O gives 1:1 H₂ to H₂O. Moles H₂ = 4.0 ÷ 2.0 = 2.0 mol → 2.0 mol H₂O × 18 g/mol = 36 g.
Correct Answer
A36 g
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