Respuesta :

3.6*10^20 atoms* (1 mol/ (6.02*10^23 atoms))= 6.0*10^(-4) mol.

6.0*10^(-4) mol* (28.1 g/ 1 mol)= 1.7*10^(-2) g.

Note that the units cancel out so you get the answer.

The final answer is 1.7*10^(-2) g Si.