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प्रश्न
Why are the following metals not used in the lab. preparation of hydrogen?
aluminium
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उत्तर
Aluminium forms a protective coating of Al2O3 due to its great affinity for oxygen. So, it does not give hydrogen with acid after the reaction has occurred for some time.
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संबंधित प्रश्न
Name the following:
Two metals which give hydrogen with cold water.
Which test should be made before collecting hydrogen in a gas jar?
Why are the following metals not used in the lab. preparation of hydrogen?
sodium
Correct the following statement:
Hydrogen is separated from CO by passing the mixture through caustic potash solution.
Select the correct options for the following statement:
A metal which reacts with water to give a metallic hydroxide & liberate hydrogen.
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 with dilute acids
Magnesium - Mg + 2HCl → ______+ _______ [g]
Account for the following fact:
Though lead is above hydrogen in the activity series, it does not react with dilute hydrochloric acid or dilutes sulphuric acid.
Give a balanced equation for obtaining hydrogen from?
Steam using a trivalent metal
State the reactant added to hydrogen to obtain the respective product in following case.
Ammonia
