Salt Analysis and Qualitative Analysis Mock Test

MOCK TEST SECTION - I : STRAIGHT OBJECTIVE TYPE 1. 2. Zinc pieces are added to acidified solution of SO3–2. AGs liberated can : (A) turn lead acetate paper black (B) turns lime water milky (C) gives both of the above tests (C) gives none of the above tests A sodium salt on treatment with MgCl2 gives white precipitate only on heating. The anion of the sodium salt is : (A) HCO3– 3. (C) NO3– (D) SO4–2 An aqueous blue coloured solution of a transition metal sulphate reacts with H2S to give a black precipitate. The black precipitate dissolves in 50% nitric acid forming a blue coloured solution. The blue solution on treatment with KI in weakly acidic medium turns yellow/brown and produces a white precipitate. Identify the transition metal ion from the following ions ? (A) Co+2 4. (B) CO3–2 (B) Cu+2 (C) Hg+2 (D) Pb+2 A 0.1 M solution of a certain cation will form a precipitate with 0.1 M solution of all these anions ; OH–, CO3–2, Cl–, SO4–2. Which cation fits in the description ? (A) Ba+2 5. (B) Fe+2 (B) Cu+ (B) Bi+3 (D) Sn+2 (C) Pb+2 (D) Cu+ Fe+2 does not give prussian blue colour with K4[Fe(CN)6], but on its reaction with (X), prussian blue colour appears. (X) can be : (A) MnO4– / H+ 8. (C) Ag+ A metal nitrate reacts with KI to give a black precipitate which on addition of excess of KI is converted into orange colour solution. The cation of the metal nitrate is : (A) Hg+2 7. (D) Pb+2 The ion that cannot be precipitated by both HCl and H2S is (A) Pb+2 6. (C) Mg+2 (B) H2SO4 (C) NH3 (D) All true To increase significantly the concentration of free Zn ion in a solution of complex ion [Zn(NH3)4]+2 +2 Zn2+ (aq) + 4NH3 (aq) ƒ [Zn(NH3)4]2+ (aq) add to the solution some : (A) H2O 9. (C) NH3 (D) NH4Cl(aq) A black coloured sulphide is insoluble in conc. HCl but dissolves when KClO3 is added. The solution on treatment with potassium cyanide gives a buff or light pink coloured precipitate which dissolves in excess of this reagent forming a yellowish brown solution. The sulphide is : (A) CoS 10. (B) HCl(aq) (B) ZnS (C) NiS (D) MnS A coloured precipitate is obtained when H2S gas is passed through an aqueous solution of salt in presence of ammonium hydroxide. The precipitate dissolves in dilute HCl and reacts with NaOH to give a white precipitate which on standing turns into brown/black precipitate. The brown/black precipitate on fusion with KNO3 and Na2CO3 gives green coloured compound. The cation of the salt is : (A) Co+2 (B) Mg+2 (C) Ni+2 (D) Mn+2 SALT ANALYSIS AND QUALITATIVE ANALYSIS 11. Intense blue precipitate of Fe4[Fe(CN)6]3 and sodium hydroxide solution when mixed gives : (A) Soluble prussian blue (B) reddish-brown precipitate (C) deep-red colouration (D) turnbull’s blue SECTION - II : MULTIPLE CORRECT ANSWER TYPE 12. Which of the following statement(s) is/are true ? (A) Soluble bicarbonates gives white precipitate with MgCl2 in cold. (B) Soluble calcium bicarbonate gives white precipitate with dil. ammonium solution. (C) All bicarbonates are generally soluble in water. (D) Hg(II) chloride forms a reddish brown precipitate in a solution of soluble carbonate. 13. Each of these solution is added to a mixture of aqueous solution of iodide and chloroform, separately. Which will give a positive test for iodine when the solutions are vigorously mixed ? (A) NaCl solution 14. (B) NaBr solution (C) chlorine water (D) bromine water Identify the incorrect reaction (s):  2CrO2Cl2 + 2Na2SO4 + K2SO4 + 3H2O (A) K2Cr2O7 + 4NaCl + 3H2SO4 (conc.)   3I2 + Cr2(SO4)3 + 4K2SO4 + 7H2O (B) K2Cr2O7 + 6 KI + 7H2SO4 (conc.)   2CrO2Cl + 2Ag2SO4 + K2SO4 + 3H2O (C) K2Cr2O7 + 4AgCl + 3H2SO4 (conc.)   NaHSO4 + MnSO4 + HCl + H2O + 1/2O2 (D) MnO2 + NaCl + 2H2SO4 (conc.)  15. Which of the following compound on treatment with a solution of HgCl2 first gives a white precipitate and then a grey precipitate ? (A) H3PO2 16. (B) SnCl2 (C) KI (D) NH3 An organic lewis acid [X] gives gelatinous white precipitate with NH4OH in presence of NH4Cl. [X] will respond to which of the following characteristics ? (A) X fumes in moist air. (B) X on heating with solid K2Cr2O7 and conc. H2SO4 gives deep red fumes. (C) Xo on addition of excess NaOH gives white precipitate. (D) X on heating with Na2CO3 and then cobalt nitrate gives a blue bead in oxidising flame. 17. The reagents, ammonium chloride and aqueous ammonia will precipitate : (A) Bi+3 18. (B) Pb+2 (C) Mg+2 (D)Fe+3 Which of the following statement(s) is/are true? (A) In a mixture of Sr+2 and Ca+2, ammonium sulphate precipitates only Sr+2 as SrSO4 but CaSO4 dissolves in ammonium sulphate forming a soluble complex. (B) Barium chromate is insoluble in dilute acetic acid. (C) Cr(OH)3 is soluble in NaOH and Br2 water while Fe(OH)3 is insoluble. (D) Cu and Cd separation is based upon the fact that in presence of excess KCN, only Cd is precipitated as sulphide on passing H2S. SECTION - III : ASSERTION AND REASON TYPE 19. Statement - 1: A very dilute acidic solution of Cd+2 and Ni+2 gives a yellow precipitate of CdS on passing hydrogen sulphide gas. Statement - 2 : Solubility products (Ksp) of CdS is less than that of NiS. (A) Statement-1 is true, Statement-2 is true ; Statement-2 is a correct explanation for Statement-1. (B) Statement-1 is true, Statement-2 is true ; Statement-2 is NOT a correct explanation for Statement-1. (C) Statement-1 is true, Statement-2 is false. (D) Statement-1 is false, Statement-2 is true. 20. Statement - 1 : No yellow precipitate is formed when an excess of more concentrated (6M) solution of KI is added to a solution containing Pb+2 ions. Statement - 2 : Yellow precipitate of PbCl2 does not dissolve in excess of dilute solution of KI. (A) Statement-1 is true, Statement-2 is true ; Statement-2 is a correct explanation for Statement-1. (B) Statement-1 is true, Statement-2 is true ; Statement-2 is NOT a correct explanation for Statement-1. (C) Statement-1 is true, Statement-2 is false. (D) Statement-1 is false, Statement-2 is true. 21. Statement - 1 : In very dilute solution of strontium ions, yellow precipitate of SrCrO4 is formed with CrO4–2 ions. Statement - 2 : The SrCrO4 precipitate is appreciably soluble in water, therefore, no precipitation occurs when water is taken in large quantity. (A) Statement-1 is true, Statement-2 is true ; Statement-2 is a correct explanation for Statement-1. (B) Statement-1 is true, Statement-2 is true ; Statement-2 is NOT a correct explanation for Statement-1. (C) Statement-1 is true, Statement-2 is false. (D) Statement-1 is false, Statement-2 is true. 22. Statement - 1 : Addition of ammonium chloride to a solution containing ferric and magnesium ions is essential for selective precipitation of ferric hydroxide by aqueous ammonia. Statement - 2 : The function of NH4Cl is to suppress the ionization of NH4OH by common ion effect and thus prevents the precipitation of Mg(OH)2 because Ksp of Mg(OH)2 is high. (A) Statement-1 is true, Statement-2 is true ; Statement-2 is a correct explanation for Statement-1. (B) Statement-1 is true, Statement-2 is true ; Statement-2 is NOT a correct explanation for Statement-1. (C) Statement-1 is true, Statement-2 is false. (D) Statement-1 is false, Statement-2 is true. SECTION - IV : COMPREHENSION TYPE Read the following comprehensions carefully and answer the questions. Comprehension # 1 A black coloured compound (A) on reaction with dil. H2SO4 gives a gas (B) which on passing in a solution of an acid (C) gives a white turbidity (D). Gas (B) when passed in an acidified solution of a compound (E) gives a black precipitate (F) which is soluble in hot concentrated (C). After boiling this solution when excess of ammonia solution is added, a blue coloured compound (G) is formed. To the solution of (E), on addition of acetic acid and aq. SALT ANALYSIS AND QUALITATIVE ANALYSIS potassium ferrocyanide, a chocolate brown precipitate (H) is formed. On addition of an aqueous solution of BaCl 2 to an aqueous solution of (E) white precipitate insoluble in HNO3 is obtained. 23. Black coloured compound (A) is : (A) PbS 24. (B) CuS (C) AgS (D) All of these To which of the following property, the compound (E) will respond ? (A) It gives white precipitate with (CH3COO)2Pb solution soluble in ammonium acetate. (B) It gives dirty white precipitate with KI. (C) Its hydrated salts effloresces (D) All of these. 25. The gas (B) on passing through an acid (C) gives a white turbidity (D) because (A) gas (B) acts as an oxidising agent (B) gas (B) acts as an reducing agent (C) acid (C) acts as an oxidising agent (D) (B) and (C) both. 26. When a piece of iron or zinc is added to the solution of a compound (F) in hot concentrated (C) acid: (A) a reddish brown precipitate is formed (B) a white precipitate is formed (C) a black precipitate is formed (D) none of these Comprehension # 2  Products [Ag(NH3)2]+ + NH2 – NH2. H2SO4 (Saturated solution)  27. Which of the following the products obtained in the above chemical reaction ? (A) A gas is obtained which produces white dense fumes with a glass rod dipped in dilute HCl. (B) A salt is obtained which also gives the same gas (option A) with sodium hydroxide. (C) A gas is liberated which is also obtained by heating ammonium dichromate. (D) All of these. 28. The above reaction describes about __________. (A) Gutzeit’s test 29. (B) Marsh’s test (C) Silver mirror test Which of the following statement is true ? (A) Silver sulphate is produced as one of the products. (B) Silver nitride is obtained as one of the products (D) Lake test SECTION - V : SUBJECTIVE TYPE 30. A mixture of two inorganic salts gives following reactivity : (i) Mixture on reaction with dil. H2SO4 produces suffocating gas which turns acidified potassium dichromate solution green. (ii) Mixture on reaction with conc. H2SO4 gives reddish brown gas and on adding paper pellets the evolution of reddish brown vapours becomes brisk. (iii) Original solution of mixture gives white ppt. with dil HCl which is soluble in ammonium hydroxide forming a soluble complex. The soluble complex gives white precipitate with HNO3 and yellow precipitate with KI solution. (iv) The filtrate obtained after separating the white precipitate also gives white precipitate with H 2S in presence of NH4Cl and NH4OH. The solution of white precipitate in dil. HCl again gives white precipitate with excess of potassium ferrocyanide solution. Identify the cations and anions present in the mixture. 31. A mixture consists (A) (yellow solid) and (B) (colourless solid). (i) Mixture gives lilac colour in flame (ii) Mixture gives black precipitate on passing H2S which is soluble only in aquaregia. (iii) Black precipitate solution in aqua-regia, on adding SnCl2 gives greyish black precipitate. (iv) The salt solution with NH4OH gives a brown precipitate. (v) The sodium extract of the salt with CCl4/Cl2 gives a violet layer. (vi) The sodium extract gives bright yellow precipitate with AgNO3, very slightly soluble in concentrated ammonia. Identify the cation and anion present in (A) and (B) ? MOCK-TEST 1. A 2. A 3. 13. C,D 14. C, D 23. D 24. D B 4. D 15. A,B 25. D 26. A 5. D 6. B 7. A 8. B 9. 16. A, B, D 17. A, B, D 18. A,B,C,D 27. D 28. C 29. D A 10. D 11. B 12. B, C, D 19. A 20. B 21. D 22. A