Here's how to calculate the number of atoms in 0.543 mol of silicon:

1. Avogadro's Number

* Avogadro's number tells us the number of particles (atoms, molecules, etc.) in one mole of a substance. It's a constant: 6.022 x 10^23 particles/mol.

2. Calculation

* Step 1: Multiply the moles of silicon by Avogadro's number:

0.543 mol Si * (6.022 x 10^23 atoms Si / 1 mol Si) = 3.27 x 10^23 atoms Si

Answer: There are approximately 3.27 x 10^23 atoms of silicon in 0.543 mol.