you are given aluminium oxide sodium hydroxide diluted hydrochloric acid come sulphuric acid and Zink metal using those chemicals. a) how do you prepare hydrogen gas? b) how do you show that aluminium oxide is an amphoteric oxide?
Answers
Answer:
Metals form respective salts when react with dilute acid.
Metal + dil. acid ⇨ Metal salt + Hydrogen
Reaction of sodium metal with dilute acid: Sodium metal gives sodium chloride and hydrogen gas when it reacts with dilute hydrochloric acid.
2Na + 2HCl ⇨ 2NaCl + H2
Reaction of potassium with dilute sulphuric acid: Potassium sulphate and hydrogen gas are formed when potassium reacts with dilute sulphuric acid.
2K + H2SO4 ⇨ K2SO4 + H2Reaction of magnesium metal with dilute hydrochloric acid: Magnesium chloride and hydrogen gas are formed when magnesium reacts with dilute hydrochloric acid.
Mg + 2HCl ⇨ MgCl2 + H2
Reaction of aluminium with dilute hydrochloric acid: Aluminium chloride and hydrogen gas are formed.
2Al + 6HCl ⇨ 2AlCl3 + 3H2
Reaction of zinc with dilute sulphuric acid: Zinc sulphate and hydrogen gas are formed when zinc reacts with dilute sulphuric acid. This method is used in laboratory to produce hydrogen gas.
Zn + H2SO4 ⇨ ZnSO4 + H2
CopperCopper, gold and silver are known as noble metals. These do not react with water or dilute acids.