Answer:
1.67 × 10⁻¹⁰m is the answer.
Explanation:
Given,
4 × 10⁻⁷m thick
2400 atoms thick
therefore 1 atom,
Diameter = 4 × 10⁻⁷/2400
d = 4000 × 10⁻¹⁰/2400
d = 1.67 × 10⁻¹⁰m
∴ diameter of 1 gold atom (3 significant figures) = 1.67 × 10⁻¹⁰m