Advertisements
Advertisements
Question
How can these impurities be removed?
Advertisements
Solution
- The impurities can be removed from hydrogen by passing it through
- Silver nitrate solution to remove arsine and phosphine.
AsH3 + 6AgNO3 → Ag3As + 3AgNO3 + 3HNO3
PH3 + 6AgNO3 → Ag3P + 3AgNO3 + 3HNO3
- Lead nitrate solution to remove hydrogensulphide.
Pb(NO3)2 + H2S → Pbs + 2HNO3
- Caustic potash solution to remove sulphur dioxide, carbon dioxide and oxides of nitrogen.
SO2 + 2KOH → K2SO3 + H2O
CO2 + 2KOH→ K2CO3+ H2O
2NO2 + 2KOH →KNO2 + KNO3 + H2O
- A drying agent used to dry the gas. Common drying agents such as fused calcium chloride, caustic potash stick and phosphorus pentoxide remove water vapor.
So, the gas is purified and dried and then collected over mercury because mercury does not react with it.
APPEARS IN
RELATED QUESTIONS
Name the following:
A metal which liberates hydrogen only when steam is passed over red hot metal.
Name the chemicals required to prepare hydrogen gas in the laboratory.
Draw a neat and well-labelled diagram for the laboratory preparation of hydrogen.
How would you show that hydrogen is a non-supporter of combustion?
FILL IN THE BLANK
Sodium liberates hydrogen when treated with cold .............
TRUE \ FALSE
Lead reacts briskly with dilute hydrochloric acid to form hydrogen.
How would you show that hydrogen is lighter than air?
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.
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 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.
Select the correct answer from the symbol in the bracket.
The element which forms a diatomic molecule.
The diagram represent the preparation and collection of hydrogen by a standard
laboratory method.

State what is added through the thistle funnel ‘Y’
The diagram represent the preparation and collection of hydrogen by a standard laboratory method.

State, why hydrogen is collected after all the air in the apparatus, is allowed to escape.
The diagram represent the preparation and collection of hydrogen by a standard laboratory method.

Name a gas other than hydrogen collected by the same method.
