Concept:The mole is a standardized unit of count. Regardless of the substance's identity, complexity, or mass, one mole always contains the exact same number of independent structural entities.
Formula:$$ \text{Molecules} = n \times N_A $$
Solution:- Ethanol is a molecule (\( \text{C}_2\text{H}_5\text{OH} \)). Ethane is also a molecule (\( \text{C}_2\text{H}_6 \)).
- Since we have exactly 1.0 mole of each substance, Avogadro's law dictates that both samples must contain exactly \( 6.022 \times 10^{23} \) molecules.
- Therefore, they have a perfectly equal number of molecules.
Why other options are incorrect:- Mass: Ethanol is much heavier (46 g/mol) than ethane (30 g/mol) due to the oxygen atom.
- Number of atoms: Ethanol has 9 atoms per molecule, while ethane has 8. They do not share equal atom counts.
- Number of electrons: Ethanol possesses more electrons because oxygen adds an extra 8 electrons compared to ethane's structure.
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