4.5 x 10^25 atoms of nickel equal how many moles?

A) 27 mol

B) 2.7 x 10^48 mol

C) 0.75 mol

D) 75 mol

Hello!

To find the number of moles in 4.5 x 10^25 atoms, we need to divide the total number of number by Avogadro's number. His number is 6.02 x 10^23 atoms. This number represents the number of atoms in one mole.

(4.5 x 10^25 atoms) / (6.02 x 10^23) ≈ 74.75083056

Using significant figures, there are about 75 moles in 4.5 x 10^25 atoms of nickel, which is choice D.