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प्रश्न
State how hydrogen occurs in the free state. Name three compounds containing hydrogen in the combined state.
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उत्तर
- In free state : In traces in the earth’s crust and atmosphere and in volcanic gases. It is also found in huge amount in the interior of the sun.
- In combined state : In organic compounds, plant and animals, in acids, in water.
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संबंधित प्रश्न
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 |
For laboratory preparation of hydrogen, give the following:
chemical equation
Why are the following metals not used in the lab. preparation of hydrogen?
aluminium
Complete and balance the following reaction.
Fe + H2O →_____________ +___________
Complete and balance the equation:
[General method]
Reactions of active metals - cold water
Sodium - 2Na + 2H2O → ______+ _______ [g]
Complete and balance the equation:
[General method]
Reactions of metals - alkali [conc. soln.]
Zinc - Zn + 2NaOH → ______ + _______ [g]
Zn + 2KOH → ____ + _____ [g]
Complete and balance the equation:
[General method]
Reactions of metals - alkali [conc. soln.]
Lead - Pb + 2NaOH → ______ + _______ [g]
How did the name ‘hydrogen’ originate? How does hydrogen occur in the combined state?
Give a balanced equation for obtaining hydrogen from?
Steam using a metal – and the reaction is reversible.
Select the correct answer to the reactant added, to give the product in the preparation of hydrogen gas.
\[\ce{NaAlO2 + H2}\]
