Chemistry
Which metal is preferred for the preparation of hydrogen
(i) from water?
(ii) from acid?
Answer
(i) Reactive metals like sodium react with cold water forming their corresponding oxides and evolving hydrogen.
2Na + 2H2O ⟶2NaOH + H2 ↑
Sodium amalgam (alloy of sodium and mercury) react smoothly with water. Therefore, hydrogen can be safely prepared from this amalgam.
(ii) Zinc reacts with acids liberating hydrogen gas and forming their respective salts.
Zn + 2HCl ⟶ ZnCl2 + H2 ↑
Related Questions
State some sources of hydrogen.
Compare hydrogen and halogens on the basis of :
(i) Physical state
(ii) ion formation
(iii) valency
(iv) reaction with oxygen
(i) Write the reaction of steam with red hot iron.
(ii) Why is this reaction considered a reversible reaction?
(iii) How can the reaction proceed continuously?
Why are zinc and aluminium considered to have a unique nature. Give balanced equations to support your answer.