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प्रश्न
In the laboratory preparation of hydrogen from zinc & dilute hydrocholoric acid – state a reason for the collecting the hydrogen by downward displacement of water and not air & collecting it after all the air in the apparatus is allowed to escape.
उत्तर
Hydrogen is collected by downward displacement of water as it is slightly soluble in water and in air it form explosive mixture with air and also hydrogen is lighter than air.
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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.
Name the following:
A metal which liberates hydrogen only when steam is passed over red hot metal.
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.
Complete and balance the equation:
[Laboratory method]
By action of dilute acid on zinc
Zinc - Zn + 2HCl → _____ + _____ [g]
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.
Give a reason for the following.
Nitric acid in the dilute form is not used in the laboratory preparation of hydrogen from metals.
Name the following.
A gaseous reducing agent which is basic in nature.
The diagram represent the preparation and collection of hydrogen by a standard laboratory method.
Name a solution which absorbs the impurity – `"H"_2"S"`