Page 39 - Chemistry ICSE Class IX
P. 39
The Language of Chemistry 27
(f) Lead nitrate on heating decomposes to give lead oxide, nitrogen dioxide and oxygen.
(g) Potassium chlorate on heating decomposes to give potassium chloride and oxygen gas.
(h) Methane (CH ) burns in air to give carbon dioxide, water and heat is evolved.
4
(i) White precipitate of silver chloride is formed on adding a solution of sodium chloride to silver nitrate
solution.
(j) The colour of potassium permanganate gets decolourised when added to an acidi ed solution of ferrous
sulphate.
(k) Phosphorus reacts with chlorine to give phosphorus pentachloride.
(l) Ferric oxide reacts with sulphuric acid to give ferric sulphate and water.
(m) Sulphur trioxide reacts with water to give sulphuric acid.
(n) Magnesium nitride reacts with water to produce magnesium hydroxide and ammonia.
(o) Magnesium burns in carbon dioxide to form magnesium oxide and carbon.
(p) Hydrogen gas combines with nitrogen to form ammonia.
(q) Hydrogen sulphide gas burns in air to give water and sulphur dioxide.
(r) Barium chloride reacts with aluminium sulphate to give aluminium chloride and precipitate of barium
sulphate.
(s) Potassium metal reacts with water to give potassium hydroxide and hydrogen gas.
(t) Aqueous solutions of sulphuric acid and sodium hydroxide react to form aqueous sodium sulphate and
water.
(u) Phosphorus burns in chlorine gas to form phosphorus pentachloride.
33. Balance the following chemical equations:
(a) HNO 3 + Ca(OH) o Ca(NO ) + H O
3 2
2
2
(b) NaOH + H SO o Na SO 4 + H O
2
4
2
2
(c) NaCl + AgNO o AgCl + NaNO 3
3
(d) BaCl 2 + H SO o BaSO 4 + HCl
2
4
(e) H SO (CS) + NaOH(CS) o Na SO (CS) + H O(N)
2
4
4
2
2
(f) Ba(OH) (CS) + HBr(CS) o BaBr (CS) + H O(N)
2
2
2
(g) KCN(CS) + H SO (CS) o K SO (CS) + HCN(I)
4
2
4
2
(h) Al(U) + HCl(CS) o AlCl (CS) + H (I)
2
3
(i) CH(I) + O (I) o CO (I) + H O(I)
2
2
2
34. Tick (9) the correct answer.
(i) Modern atomic symbols are based on the method proposed by
(a) Alchemists
(b) Dalton
(c) Berzelius
(d) Böhr
(ii) The symbol of argon is
(a) A
(b) Ar
(c) Ag
(d) Arg 
