Advertisements
Advertisements
Question
Hydrogen may be prepared in the laboratory by the action of a metal on an acid.
Which of the acids dilute sulphuric, concentrated sulphuric, dilute nitric acid and concentrated nitric acid would you choose? Explain why you would not use the acids you reject.
Advertisements
Solution
Dilute sulphuric acid.
Conc. nitric acid, even in its diluted form, is not used in the preparation of hydrogen from metals because it is a powerful oxidising agent and oxygen formed due to its decomposition oxidises hydrogen to give water, thus defeating the purpose of the reaction.
Conc. sulphuric acid is not used in the preparation of hydrogen as it will produce sulphur dioxide.
APPEARS IN
RELATED QUESTIONS
A metal ______ hydrogen in the reactivity series gives hydrogen with ______.
Fill in the blank
Hydrogen reacts with metal oxides to form ............and....................
Complete and balance the following reaction.
Fe + H2O →_____________ +___________
Starting from hydrogen gas how would you obtain a metal by reduction of its heated oxide.
Select the correct options for the following statement:
The metal which reacts with steam liberating hydrogen & the reaction is reversible.
On heating which of the following substances i.e. copper carbonate, zinc carbonate, washing soda, copper sulphate, zinc nitrate, copper nitrate, lead nitrate, ammonium chloride and ammonium dichromate – relate to the reaction given below.
A white substance which leaves an amphoteric oxide as a residue [whose colour varies in the heated and in the cold state] and evolves a gas which turns lime water milky.
Complete and balance the equation:
[General method]
Reactions of metals with steam
Aluminium - 2Al + 3H2O → ______+ _______ [g]
Complete and balance the equation:
[General method]
Reactions of metals with steam
Iron - 3Fe + 4H2O ⇌ ______+ _______ [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.
