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प्रश्न
Starting from zinc how would you obtain hydrogen using an alkali.
[Give balanced equation & name the product formed in the case other than hydrogen].
Name a metal which will not react with the reactants above to give hydrogen.
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उत्तर
An alkali : Zn, Pb react with concentrated alkali on boiling to give the corresponding metallic salt and liberate hydrogen.
\[\ce{\underset{\text{Zinc}}{Zn} + 2NaOH ->\underset{\text{Sodium zincate}}{Na2ZnO2} + H2}\]
\[\ce{Pb + 2NaOH ->\underset{\text{Sodium plumbite}}{Na2PbO2} + H2}\]
Silver (Hg) will not react with alkali to give hydrogen.
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संबंधित प्रश्न
Indicate which of the following statement is true and which is false:
Nitric acid cannot be used to prepare hydrogen by its action on active metals.
Name the following:
A metal which liberates hydrogen only when steam is passed over red hot metal.
How would you show that hydrogen is a non-supporter of combustion?
FILL IN THE BLANK
Sodium liberates hydrogen when treated with cold .............
FILL IN THE BLANK
........................ zinc is preferred over pure zinc in the laboratory preparation of hydrogen.
TRUE \ FALSE
Lead reacts briskly with dilute hydrochloric acid to form hydrogen.
Why is granulated zinc preferred in the laboratory preparation of hydrogen?
Name the impurities present in hydrogen prepared in the laboratory.
How can these impurities be removed?
Under what conditions can hydrogen be made to combine with chlorine?
Name the products and write the equation for the reaction.
Starting from zinc how would you obtain hydrogen using a dilute acid.
[Give balanced equation & name the product formed in the case other than hydrogen].
Name a metal which will not react with the reactants above to give hydrogen.
Draw neat labelled diagrams for two different experiments to prove that – hydrogen is lighter than air.
Give balanced equation for the following conversion:
Acidified water to hydrogen – by electrolysis.
Give reason for the following:
Copper does not displace hydrogen from dilute hydrochloric acid, but zinc does.
Give a balanced equation for the following conversions sodium plumbite from lead.
Give a balanced equation for the following conversions sodium aluminate from aluminium.
In the laboratory preparation of hydrogen from zinc and dil. acid. Give a reason for the following:
The complete apparatus is air-tight.
The diagram represent the preparation and collection of hydrogen by a standard laboratory method.

Name a solution which absorbs the impurity – `"H"_2"S"`
