Which of the following samples contains the largest number of atoms? (H = 1, C = 12, O = 16)

Answer: B

Atoms in units of

N_{A}

= moles

\times

atoms per molecule:

H X_{2}

2.0,

CH X_{4}

5.0,

H X_{2} O

3.0,

CO X_{2}

1.5. The methane sample is largest.

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