Comparing moles of hydrogen atoms across options

Steps:

• Butane (C₄H₁₀) has 10 H atoms per molecule; 0.10 mol gives 1.0 mol H atoms.
• But-2-ene (C₄H₈) has 8 H atoms per molecule; 0.20 mol gives 1.6 mol H atoms.
• Hydrogen molecules (H₂) have 2 H atoms per molecule; 1.00 mol gives 2.0 mol H atoms.
• Option D is exactly 1 mol (6.02 × 10²³) of H atoms.
• Multiply each by Avogadro's number (6.02 × 10²³) and compare: C has the largest total (1.204 × 10²⁴ H atoms).

Why C is correct:

• One mole of H₂ contains 2 moles of H atoms by the molecular formula H₂, yielding twice Avogadro's number of H atoms.

Why the others are wrong:

• A: 0.10 mol C₄H₁₀ yields only 1 mol H atoms, half of C.
• B: 0.20 mol C₄H₈ yields 1.6 mol H atoms, less than C's 2 mol.
• D: Directly 1 mol H atoms, fewer than C's 2 mol.

Final answer: C