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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
Name the following:
A metal which liberates hydrogen only when steam is passed over red hot metal.
Name the following:
A metallic oxide which can be reduced into metal by hydrogen.
Multiple Choice Question
In metal activity series the more reactive metals are at
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.
Give a test to identify hydrogen ?
How can these impurities be removed?
Give reason:
Apparatus for laboratory preparation of hydrogen should be airtight and away from a naked flame.
How would you show that hydrogen is lighter than air?
Starting from zinc how would you obtain hydrogen using Steam.
[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.
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.
In the laboratory preparation of hydrogen from zinc & dilute hydrocholoric acid – state a reason for the addition of traces of copper [II] sulphate to the reaction medium.
Draw neat labelled diagrams for two different experiments to prove that – hydrogen is lighter than air.
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.
In the laboratory preparation of hydrogen from zinc and dil. acid. Give a reason for the following:
The lower end of the thistle funnel should dip below the level of the acid in the flask.
In the laboratory preparation of hydrogen from zinc and dil. acid. Give a reason for the following:
Hydrogen is not collected over air.
Give a reason for the following.
Nitric acid in the dilute form is not used in the laboratory preparation of hydrogen from metals.
Select the correct answer from the symbol in the bracket.
The element which forms a diatomic molecule.
