A silicon (atomic weight=28) chip used in an integrated circuit of a microcomputer has a mass of 5.68 mg. How many silicon (Si) atoms are present in this chip.

Question

$\begin{array}{1 1}(a)\;2.02\times 10^{-4}&(b)\;1.22\times 10^{20}\\(c)\;12.2\times 10^{20}&(d)\;122\times 10^{20}\end{array}$