What is the mass of 10 moles of sodium sulphite, and how is it calculated?
ChemistryClass 10CBSEAnswered 28 May 2026
Answer
The mass of 10 moles of sodium sulphite (Na₂SO₃) is 1260 g.
Given:
- Formula: Na₂SO₃
- Number of moles = 10
Molar Mass Calculation:
| Element | Atoms | Atomic Mass | Total |
|---|---|---|---|
| Na | 2 | 23 | 46 |
| S | 1 | 32 | 32 |
| O | 3 | 16 | 48 |
| Molar Mass | 126 g/mol |
Formula: Mass = Moles × Molar Mass Mass = 10 × 126 = 1260 g
- Common mistake: Students often write SO₄ (sulphate) instead of SO₃ (sulphite) — always check the ion name carefully.
The molar mass of Na₂SO₃ is 126 g/mol, so 10 moles weigh 1260 g.