$0.270nm · (m/ 1 x 10^6nm) · (1000mm/1m) = 0.000270 mm per atom$ $1.0 mm · (atom/ 0.000270mm) = 3.7x10^3 atoms Au$
Work Step by Step
The radius of a gold atom is 1.35 Angstroms. The diameter is 2.70. Use conversion factors to find the mm per atom. Divide 1.0mm by that number to determine how many atoms of gold can be lined up side by side.