State your observations when:
(a) lead nitrate solution and sodium chloride solution are mixed.
(b) zinc chloride solution, zinc nitrate solution and zinc sulphate solutions are added individually to
(i) barium chloride solution,
(ii) lead nitrate solution.
(c) Decomposition of bicarbonates by dil. H2SO4
2NaHCO3 + H2SO4 ⟶ Na2SO4 + 2H2O + 2CO2
2KHCO3 + H2SO4 ⟶ K2SO4 + 2H2O + 2CO2
(d) Zinc carbonate is heated strongly.
(e) a piece of moist blue litmus paper is introduced in a jar of chlorine.
(f) paper soaked in potassium permanganate solution — is introduced in each case into a jar of sulphur dioxide.
(g) When moist starch iodide paper is introduced into chlorine gas.
(a) When lead nitrate solution is mixed with sodium chloride solution, a white precipitate of lead chloride is seen and the soluble salt sodium nitrate is formed.
2NaCl + Pb(NO3)2 ⟶ 2Na(NO3)2 + PbCl2↓
Precipitate of lead chloride and sodium nitrate are formed.
(b)
| Zinc Chloride Solution | Zinc Nitrate Solution | Zinc Sulphate Solution | |
|---|---|---|---|
| Barium Chloride Solution | No reaction | No ppt. observed | White ppt. is obtained which is insoluble in mineral acid. |
| Lead Nitrate Solution | White ppt. is obtained | No reaction | No ppt. observed |
(c) Carbon dioxide gas is evolved with brisk effervescence which turns blue litmus red and extinguishes a burning wooden splinter.
(d) When zinc carbonate is strongly heated, the light amorphous white solid, changes to pale yellow colour.
ZnCO3 ZnO + CO2
(e) Moist blue litmus turns red and then may eventually get bleached.
(f) Sulphur dioxide turns potassium permanganate from pink to clear colourless.
2KMnO4 + 2H2O + 5SO2 ⟶ K2SO4 + 2MnSO4 + 2H2SO4
(g) Chlorine gas turns moist starch iodide paper blue black.
Cl2 + 2KI ⟶ 2KCl + I2
[Starch + I2 ⟶ blue black colour]