The radius of a niobium atom is 131 pm. How many niobium atoms would have to be laid side by side to span a distance of 4.53 mm?

atoms

2 answers

radius is 131 pm
diameter is 2*131 pm
2*131 pm x (1 mm/10^9) x #atoms = 4.53 mm
Solve for # atoms
1.04x10^-7