Question

How many moles are in 7.00E24 atoms of Ca?

Answer 1

Explanation:

In chemistry, a mole is the base unit of the amount of substance in a system containing elementary entities (atoms, molecules, ions, electrons), and one mole of substance corresponds to the Avogadro's constant or $6.023 \ \times \ 10^{23}$  entities. The stoichiometry equation that relates the amount of substance into the measurement in moles is

                                                           $n \ = \ \displaystyle\frac{\alpha}{N_{A}}$,

where $n$ is the number of moles, $\alpha$ is the amount of substance and $N_{A}$ is the Avogadro's constant.

Therefore,

                                           $n \ = \ \displaystyle\frac{7.00 \ \times \ 10^{24} \ \text{atoms}}{6.023 \ \times \ 10^{23} \ \text{atoms mol}^{-1}} \\ \\ n \ = \ 11.624 \ \text{mol}$.