A 3.0 g sample of `Na_(2)CO_(3).H_(2)O` is heated to a constant mass. How much anhydrous salt remains ?

Explanation

To solve the question of how much anhydrous sodium carbonate (Na₂CO₃) remains after heating a 3.0 g sample of sodium carbonate monohydrate (Na₂CO₃·H₂O), we can follow these steps:

### Step 1: Determine the Molar Mass of Na₂CO₃·H₂O
First, we need to calculate the molar mass of the hydrated salt (Na₂CO₃·H₂O).

- Sodium (Na): 23 g/mol × 2 = 46 g/mol
- Carbon (C): 12 g/mol × 1 = 12 g/mol
- Oxygen (O): 16 g/mol × 3 = 48 g/mol (from Na₂CO₃)
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