Here's how to calculate the moles of sodium sulfate (Na₂SO₄) present in 0.1000 grams:

1. Find the molar mass of Na₂SO₄:

* Na: 22.99 g/mol (x 2 = 45.98 g/mol)

* S: 32.06 g/mol

* O: 16.00 g/mol (x 4 = 64.00 g/mol)

* Total molar mass = 45.98 + 32.06 + 64.00 = 142.04 g/mol

2. Use the formula: moles = mass / molar mass

* moles = 0.1000 g / 142.04 g/mol

* moles ≈ 0.000704 mol

Therefore, approximately 0.000704 moles of sodium sulfate are present in 0.1000 grams.