AP Chemistrymediummcq1 pt
Which sample contains the largest number of molecules?
A.2.0 g H₂ (molar mass 2.0 g/mol)
B.44 g CO₂ (molar mass 44 g/mol)
C.17 g NH₃ (molar mass 17 g/mol)
D.36 g H₂O (molar mass 18 g/mol)
Explanation
Core Concept
Convert each sample to moles: H₂ 1.0 mol, CO₂ 1.0 mol, NH₃ 1.0 mol, H₂O 36 ÷ 18 = 2.0 mol. More moles means more molecules, so the water sample wins.
Correct Answer
D36 g H₂O (molar mass 18 g/mol)
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