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प्रश्न
Give reason:
Apparatus for laboratory preparation of hydrogen should be airtight and away from a naked flame.
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उत्तर
Apparatus for laboratory preparation of hydrogen should be airtight and away from a naked flame because a mixture of hydrogen and air explodes violently when brought near a flame.
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संबंधित प्रश्न
Indicate which of the following statement is true and which is false:
Zinc can liberate hydrogen from water, acid and alkali solution.
Give reason for the following:
Nitric acid not used for the preparation of hydrogen gas?
Name the chemicals required to prepare hydrogen gas in the laboratory.
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.
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.
Give balanced equation for the following conversion:
Zinc to sodium zincate – using an alkali.
Give reason for the following:
In the laboratory preparation of hydrogen from zinc and dilute hydrochloric acid – the zinc used granulated zinc.
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.
In the laboratory preparation of hydrogen from zinc and dil. acid. Give a reason for the following:
Dilute nitric acid is not preferred as the reactant acid.
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.
The diagram represent the preparation and collection of hydrogen by a standard laboratory method.
State what difference will be seen if pure zinc is added in the distillation flask ‘X’ instead of granulated zinc.
