1. Find the molar mass of MgS2O3:

* Mg: 24.31 g/mol

* S: 32.06 g/mol (x2 = 64.12 g/mol)

* O: 16.00 g/mol (x3 = 48.00 g/mol)

Total molar mass = 24.31 + 64.12 + 48.00 = 136.43 g/mol

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

* moles = 211 g / 136.43 g/mol

* moles ≈ 1.55 mol

Therefore, there are approximately 1.55 moles of MgS2O3 in 211 g of the compound.