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Question
Why are the following metals not used in the lab. preparation of hydrogen?
aluminium
Solution
Aluminium forms a protective coating of Al2O3 due to its great affinity for oxygen. So, it does not give hydrogen with acid after the reaction has occurred for some time.
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RELATED QUESTIONS
Match the statements in Column A with those in Column B.
| Column A | Column B |
|
1. A metal which reacts with cold water to from hydrogen. |
1. Reduction |
| 2. A gas which is inflammable and non-supporter of combustion | 2. Hydrogenation |
|
3. A process in which vanspati ghee is prepared from vegitable oils |
3. oxidation |
|
4. The removal ofhydrogen or addition of oxygen |
4. sodium |
| 5. The addition of hydrogen or removal of oxygen | 5. Hydrogen |
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The metal used as a catalyst in hydrogenation of oils.
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\[\ce{KAlO2<-KOH->K2ZnO2}\]
