Concept:Avogadro's law fundamentally links the number of moles to the number of molecules, completely independent of the gas's mass, volume, or chemical identity.
Formula:$$ \text{Number of molecules} = n \times N_A $$
Solution:- The problem explicitly states that the samples contain the "same moles" of each gas.
- Because they have the exact same number of moles (\( n \)), multiplying by Avogadro's constant (\( N_A \)) will yield the exact same mathematical product.
- Therefore, regardless of their differing molar masses or properties, all three gas samples contain an identical number of molecules.
Why other options are incorrect:- \( \text{N}_2 \), \( \text{H}_2 \), \( \text{O}_2 \): Choosing any specific gas implies that molecular size or mass affects the particle count, which violently violates Avogadro's principle.
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