Answer:
5,440,000 atoms
Explanation:
The width (diameter) of a chromium atom is 250 pm (twice the radius). A picometer is equal to 10⁻⁹ millimeters, so the width of an atom is 250 x 10⁻⁹ mm
The number of atoms required to span of 1.36 mm is calculated as follows:
[tex]\frac{1.36}{250 x 10^-9} = 5,440,000[/tex]