Name the gas produced when sodium is added to ethanol.
How to approach this question
Recall the reaction of alcohols with reactive metals like sodium. This reaction is similar to the reaction of water with sodium. The sodium displaces one of the hydrogen atoms. Which one?
Full Answer
Hydrogen
Alcohols, like ethanol, can react with reactive alkali metals such as sodium. In this reaction, the sodium atom displaces the hydrogen atom from the hydroxyl (-OH) group of the alcohol. This produces a sodium alkoxide (in this case, sodium ethoxide) and hydrogen gas.
The word equation is:
Sodium + Ethanol → Sodium ethoxide + Hydrogen
The balanced chemical equation is:
2Na(s) + 2C₂H₅OH(l) → 2C₂H₅ONa(aq) + H₂(g)
The gas produced is hydrogen.
Common mistakes
✗ Naming another gas like oxygen or carbon dioxide.
✗ Naming one of the other products, sodium ethoxide.
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