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Moles in one nanotube
A nanotube contains 2380 carbon atoms.
The Avogadro constant is 6.02 × 10²³ per mole.
Calculate the number of moles of carbon in this nanotube.
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Marking points
- 1 Divides the number of atoms by the Avogadro constant.
- 2 Gives 3.95 × 10⁻²¹ mols to at least 2 significant figures.
Full-mark answer
Number of moles = 2380 ÷ (6.02 × 10²³) = 3.95 × 10⁻²¹ mols.
Why this answer loses marks
I multiplied the particle count by Avogadro's constant.
That reverses the conversion; moles come from dividing particle count by Avogadro's constant before using standard form.