Chemistry
Give a chemical test to distinguish between following pairs of chemicals :
(i) Lead nitrate solution and zinc nitrate solution.
(ii) Sodium chloride solution and sodium nitrate solution
Answer
(i) When NaOH is added to each of the compounds, lead nitrate forms a chalky white precipitate of lead hydroxide [Pb(OH)2] whereas a gelatinous white precipitate of zinc hydroxide [Zn(OH)2] is formed in case of zinc nitrate.
(ii) Add silver nitrate soln. to the given solns., sodium chloride reacts to form a white ppt. which is soluble in NH4OH and insoluble in dil. HNO3. The other soln. is sodium nitrate.
NaCl + AgNO3 ⟶ AgCl + NaNO3
NaNO3 + AgNO3 ⟶ no white ppt.
Related Questions
Identify the salts P and Q from the observations given below :
(i) On performing the flame test salt P produces a lilac coloured flame and it's solution gives a white precipitate with silver nitrate solution, which is soluble in ammonium hydroxide solution.
(ii) When dilute HCl is added to a salt Q, a brisk effervescence is produced and the gas turns lime water milky. When NH4OH solution is added to the above mixture [after adding dilute HCl], it produces a white precipitate which is soluble in excess NH4OH solution.
State one relevant observation - Barium chloride solution is slowly added to sodium sulphate solution.
State one observation for the following : Lead nitrate is heated strongly in a test tube.
Distinguish between the following pairs of compounds using the reagent given in the bracket.
(i) Manganese dioxide and copper [II] oxide [using conc. HCl]
(ii) Ferrous sulphate solution and ferric sulphate solution [using sodium hydroxide solution]