Answer:
2.18 × 10⁷ Au atoms
Explanation:
Step 1: Calculate the diameter of a gold atom
The diameter is twice the radius.
d = 2 × r = 2 × 144 pm = 228 pm
Step 2: Convert "d" to meters
We will use the conversion factor 1 m = 10¹² pm.
228 pm × 1 m/10¹² pm = 2.28 × 10⁻¹⁰ m
Step 3: Convert the total distance to be covered (D) to meters
We will use the conversion factor 1 m = 10³ mm.
4.97 mm × 1 m/10³ mm = 4.97 mm × 10⁻³ m
Step 4: Calculate the number of atoms of gold required
We will divide the total distance by the diameter of 1 atom of gold.
D/d = 4.97 mm × 10⁻³ m/2.28 × 10⁻¹⁰ m = 2.18 × 10⁷
