MCQ
Name the gas released at the cathode when acidulated water is electrolysed.
- AHydrogen
- BNitrogen
- COxygen
- DNone of the above
✓
Answer
- Hydrogen
Explanation:
Acidulated water is a mixture of cold water and small amount if vinegar, lemon juice or lime juice. it's just used as a soak to prevent discoloration of some fruits and vegetables that darken quikly when their cut surfaces are exposed to air. During electrolysis of acidulated water, hydrogen gas (H2) is liberated at cathode.
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$(A)$ $66.13$ $(B)$ $58.38$ $(C)$ $28.30$ $(D)$ $46.29$
$2.$ When ammonia is added to the solution, $\mathrm{pH}$ is raised to $11$ . Which half-cell reaction is affected by $\mathrm{pH}$ and by how much?
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$(D)$ $\mathrm{NH}_3$ has affected the standard reduction potential of glucose/gluconic acid electrode.
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