Here's the balanced chemical equation:
Na₂ZnO₂ + H₂S → ZnS + 2NaOH + H₂O
Explanation:
* Sodium zincate (Na₂ZnO₂) is a salt containing the zincate ion (ZnO₂²⁻).
* Hydrogen sulfide (H₂S) is a colorless, flammable gas with a characteristic rotten egg smell.
* Zinc sulfide (ZnS) is a white solid that is insoluble in water.
* Sodium hydroxide (NaOH) is a strong base.
* Water (H₂O) is a byproduct of the reaction.
Mechanism:
The reaction proceeds through a double displacement mechanism, where the zincate ion (ZnO₂²⁻) from sodium zincate reacts with the sulfide ion (S²⁻) from hydrogen sulfide. The sulfide ion replaces the oxygen atoms in the zincate ion, forming zinc sulfide. This leaves sodium ions (Na⁺) and hydroxide ions (OH⁻) in solution, which combine to form sodium hydroxide. The reaction also generates water as a byproduct.
Important Note:
The reaction is exothermic, meaning it releases heat. It's important to handle the reaction with caution as hydrogen sulfide gas is toxic and flammable.
