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प्रश्न
Distinguish by dilute sulphuric acid.
Sodium sulphide and sodium sulphite?
उत्तर
| Sodium sulphide | Sodium sulphite |
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Sodium sulphite is the sodium salt of sulphurous acid having molecular formula Na2SO3, can be made by dissolving NaOH in H2SO3. In Sodium sulphite, the oxidation state of Sulphur is +4. |
Sodium sulphite (Na2SO3) will effervesce when dilute acid is added giving off a colourless gas with a choking smell (sulphur dioxide), which, if bubbled through acidified dichromate solution will turn it green.
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With Sulphuric acid, sodium sulphide liberates H2S.
\[\ce{Na2S + H2SO4 -> Na2SO4 + H2S}\]
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With sulphuric acid, sodium sulphite liberates SO2 along with water.
\[\ce{Na2SO3 + H2SO4 -> Na2SO4 + H2O + SO2}\]
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