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InterviewSolution
This section includes InterviewSolutions, each offering curated multiple-choice questions to sharpen your knowledge and support exam preparation. Choose a topic below to get started.
| 1. |
A compound (A) is greenish crystalline salt which gave the following results `:` `i)` Addition of `BaCl_(2)` solution to solution of (A) results in the formation of a white ppt. (B), which is insoluble in dil. HCl. `ii)` On heating (A), water vapours and two oxides of sulphur, (C ) and (D) are liberated leaving a red brown residue (E). `iii)` (E) dissolves in warm conc. HCl to give a yellow solution (F). `iv)` With `H_(2)S`, the solution (F) yields a pale yellow ppt. (G), which when filtered, leaves a greenish filtrate (H). `v)` Solution (F) on treatment with thiocyanate ions gives blood red coloured compound (I). Identify the substances from (A) to (I). Yellow ppt (G) is a `:`A. Solution (F)B. Solution (H)C. A and B bothD. None of these |
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Answer» Correct Answer - A `Fe^(2+)+K_(4)[Fe(CN)_(6)]rarr`White ppt `Fe^(3+)+K_(4)[Fe(CN)_(6)]rarr` Blue colouration `Fe^(2+)+K_(4)[Fe(CN)_(6)]rarr `Blue colouration `Fe^(3+)+K_(3)[Fe(CN)_(6)]rarr ` Red - brown colouration |
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| 2. |
A compound (A) is greenish crystalline salt which gave the following results `:` `i)` Addition of `BaCl_(2)` solution to solution of (A) results in the formation of a white ppt. (B), which is insoluble in dil. HCl. `ii)` On heating (A), water vapours and two oxides of sulphur, (C ) and (D) are liberated leaving a red brown residue (E). `iii)` (E) dissolves in warm conc. HCl to give a yellow solution (F). `iv)` With `H_(2)S`, the solution (F) yields a pale yellow ppt. (G), which when filtered, leaves a greenish filtrate (H). `v)` Solution (F) on treatment with thiocyanate ions gives blood red coloured compound (I). Identify the substances from (A) to (I). Yellow ppt (G) is a `:`A. metal sulphateB. metal sulphideC. metallic precipitateD. sulphur |
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Answer» Correct Answer - D `A=FeSO_(4).7H_(2)O,B=BaSO_(4),C=SO_(2),D=SO_(3),` |
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| 3. |
A compound (A) is greenish crystalline salt which gave the following results `:` `i)` Addition of `BaCl_(2)` solution to solution of (A) results in the formation of a white ppt. (B), which is insoluble in dil. HCl. `ii)` On heating (A), water vapours and two oxides of sulphur, (C ) and (D) are liberated leaving a red brown residue (E). `iii)` (E) dissolves in warm conc. HCl to give a yellow solution (F). `iv)` With `H_(2)S`, the solution (F) yields a pale yellow ppt. (G), which when filtered, leaves a greenish filtrate (H). `v)` Solution (F) on treatment with thiocyanate ions gives blood red coloured compound (I). Identify the substances from (A) to (I). Red brown residue (E) produces metal when it is heated with I) coke`" "`II)`Al_(2)O_(3)` `III)` metal sulphide of same metal `IV)` Al metalA. I,IIB. I,IIIC. I,III,IVD. I,IV |
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Answer» Correct Answer - D `E=Fe_(2)O_(3),F=FeCl_(3)(aq.),G=`Sulphur |
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| 4. |
A compound (A) is greenish crystalline salt which gave the following results `:` `i)` Addition of `BaCl_(2)` solution to solution of (A) results in the formation of a white ppt. (B), which is insoluble in dil. HCl. `ii)` On heating (A), water vapours and two oxides of sulphur, (C ) and (D) are liberated leaving a red brown residue (E). `iii)` (E) dissolves in warm conc. HCl to give a yellow solution (F). `iv)` With `H_(2)S`, the solution (F) yields a pale yellow ppt. (G), which when filtered, leaves a greenish filtrate (H). `v)` Solution (F) on treatment with thiocyanate ions gives blood red coloured compound (I). Identify the substances from (A) to (I). Yellow ppt (G) is a `:`A. `+3,+2,+2`B. `+3,+3,+2`C. `+2,+3,+2`D. `+2,+2,+3` |
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Answer» Correct Answer - C `H=FeCl_(2),I=Fe(SCN)_(3)` |
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| 5. |
Match the reactions in Column I with nature of the reactions `//` type of the products in Column II. A. `MnO_(4)^(2-)+H^(+)rarr" "(p)"`One of the products of transition element is paramagnetic.B. `Cu^(+)(aq)rarr " "(q)` Disproportation reaction.C. `Cr_(2)O_(7)^(2-)(s)+H^(+)("conc.")+Cl^(-)(s) rarr" "(r )` One of the products central atom exhibits its highest oxidation stateD. `Fe_(2)(SO_(4))_(3)+I^(-)rarr" "(s)` In one of the products central atom exhibits its highest oxidation stat |
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Answer» Correct Answer - `(A-p,q,s);(B-p,q);(C-r,s);(D-p,r,s)` Conceptual |
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| 6. |
Match the reactions in Column I with nature of the reactions `//` type of the products in Column II. A. `O_(2)^(-)rarrO_(2)+O_(2)^(2)" "(p)` redox reactionB. `CrO_(4)^(2-)+H^(+)rarr" "(q)` One of the products has trigonal planar structureC. `MnO_(4)^(-)+NO_(2)^(-)+H^(+)rarr" "(r )` dimeric bridged tetrahdedral metal ionD. `NO_(3)^(-)+H_(2)SO_(4)+Fe^(2+)rarr" "(s)` disproportionation |
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Answer» Correct Answer - `(A-p,p,s);(B-r);(C-p,q);(D-p)` Conceptual |
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| 7. |
Match the reactions in Column I with nature of the reactions `//` type of the products in Column II. A. `O_(2)^(-)rarrO_(2)+O_(2)^(2-)" "(p)` redox reactionB. `CrO_(4)^(2-)+H^(+)rarr" "(q)` one of the products has trigonal planar structureC. `MnO_(4)^(-)+NO_(2)^(-)+H^(+)rarr" "(r) ` dimerica bridge tetrahdedral metal ionD. `NO_(3)^(-)+H_(2)SO_(4)+Fe^(2+)rarr" "(s)` disproportionation |
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Answer» Correct Answer - `(A-p,s);(B-r);(C-p,q);(D-p)` `KMnO_(4)rarrK_(2)MnO_(4)+MnO_(2)+O_(2)` `K_(2)Cr_(2)O_(7)rarrK_(2)CrO_(4)+Cr_(2)O_(3)+O_(2)` `Pb_(3)O_(4)rarrPbO+O_(2)` `Pb(NO_(3))_(2)rarrPbO+NO_(2)+O_(2)` `PbO_(2)rarrPbO+O_(2)` |
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| 8. |
Match the reactions in Column I with nature of the reactions `//` type of the products in Column II. A. `MnO_(4)^(2-)+H^(+)rarr" "(p)` One of the products of transition element is paramagneticB. `Cu^(+)(aq)rarr" "(q)` Disproportionation reaction.C. `Cr_(2)O_(7)^(2-)(s)+H^(+)("conc.")+Cl^(-)(s)" "(r)` One of the products is liberated as coloured vapours.D. `Fe_(2)(SO_(4))_(3)+I^(-)rarr" "(s)` In one of the products central atom exhibits its highest oxidation state. |
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Answer» Correct Answer - A::B::C::D `CuSO_(4),H_(2)SO_(4),KMnO_(4),K_(2)Cr_(2)O_(7),` Bleaching powder, `Cl_(2),NaNO_(2)+HCl` gives `I_(2)` |
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| 9. |
When a metal rod M is dipped into an aqueous colourless concentrated solution of compound N, the solution turns light blue. Addition of aqueous `NaCl` to the blue solution gives a white precipitate O. Addition of aqueous `NH_(3)` dissolves O and gives an intense blue solution. The compound N isA. `AgNO_(3)`B. `Zn(NO_(3))_(2)`C. `Al(NO_(3))_(2)`D. `Pb(NO_(3))_(2)` |
| Answer» Correct Answer - A | |
| 10. |
When a metal rod M is dipped into an aqueous colourless concentrated solution of compound N, the solution turns light blue. Addition of aqueous NaCl to the blue solution gives a white precipitate O. Addition of aqueous `NH_(3)` dissolves O and gives an intense blue solution. The metal rod M isA. FeB. CuC. NiD. CO |
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Answer» Correct Answer - B `underset((M))(Cu)+underset((N))(2AgNO_(3))rarrunderset(("Blue"))(Cu(NO_(3))_(2))+2Ag` `NaCl+underset(("remaining"))(AgNO_(3))rarrunderset((O))(AgCldarr)+NaNO_(3)` `2AgCl+2NH_(3)(aq)rarrunderset(("Soluble"))([Ag(NH_(3))_(2)]^(+))` `underset(("remaining"))(Cu(NO_(3))_(2))+4NH_(3)(aq)rarrunderset(("Deep blue colour"))([Cu(NH_(3))_(4)](NO_(3))_(2))` |
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| 11. |
When a metal rod M is dipped into an aqueous colourless concetrated solution of compound N, the solution turns light blue. Addition of aqueous NaCl to the blue solution gives a white precipitate O. Addition of aqueous `NH_3` dissolves O and gives an intense blue solution. Q. The final solution contains.A. `[Pb(NO_(3))_(4)]^(2+)` and `[CoCl_(4)]^(2-)`B. `[Al(NH_(3))_(2)]^(3+)` and `[Cu(NH_(3))_(4)]^(2+)`C. `[Al(NH_(3))_(2)]^(+)` and `[Cu(NH_(3))_(4)]^(2+)`D. `[Al(NH_(3))_(2)]^(+)` and `[Ni(NH_(3))_(6)]^(2+)` |
| Answer» Correct Answer - C | |
| 12. |
`K_(2)Cr_(2)O_(7)` is preferred oxidizing agent than `Na_(2)Cr_(2)O_(7)` becauseA. `Na_(2)Cr_(2)O_(7)` is hygroscopicB. `K_(2)Cr_(2)O_(7)` is hygroscopicC. `Na_(2)Cr_(2)O_(7)` is not an oxidizing agentD. `K_(2)Cr_(2)O_(7)` is oxidizing and hygroscopic |
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Answer» Correct Answer - A Due to `Na_(2)Cr_(2)O_(7)` is hygroscopic |
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| 13. |
Statement `1:` Lithophone is preferred over white lead as white pigment. Statement `2:` In the presence of `H_(2)S` present in air, white lead turns black.A. Statement 1 is True, Statement 2 is True, Statement 2 is a correct explanation for Statement 1B. Statement 1 is True, Statement 2 is True, Statement 2 is not a correct explanation for Statement 1C. Statement -1 is True, Statement -2 is FalseD. Statement -1 is False, statement -2 is True. |
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Answer» Correct Answer - A Lithophone is preferred as white pigment is presence of `H_(2)S` white lead turns Black. |
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| 14. |
Which two sets of reactants best represent the amphoteric character of `Zn(OH)_(2)`? Set `1: Zn(OH)_(2) & OH^(-)(aq)` Set `2: Zn(OH)_(2)(s)& H_(2)O(l)` Set `3: Zn(OH)_(2)(s)&H^(+)(aq)` Set `4: Zn(OH)_(2)(s)& NH_(3)(aq)`A. 1 and 2B. 1 and 3C. 2 and 4D. 3 and 4 |
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Answer» Correct Answer - B `Zn(OH)_(2)` and `H_(2)O` are Amphoterica in nature |
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| 15. |
`(NH_(4))_(2)Cr_(2)O_(7)` (ammonium dichromate) is used in fire works. The green coloured powder blown in air is:A. `Cr_(2)O_(3)`B. `CrO_(2)`C. `Cr_(2)O_(4)`D. `CrO_(3)` |
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Answer» Correct Answer - A `(NH_(4))_(2)Cr_(2)O_(7)overset(Delta)(rarr)Cr_(2)O_(3)` |
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| 16. |
`K_(2)Cr_(2)O_(7)`, on heating givesA. `Cr_(2)O_(3)`B. `K_(2)CrO_(4)`C. `O_(2)`D. All of these |
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Answer» Correct Answer - D `ZnCl_(2).2H_(2)Ounderset(Delta)(rarr)Zn(OH)Cl+HCl+H_(2)O` |
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| 17. |
`(NH_(4))_(2)Cr_(2)O_(7)` on heating liberates a gas. The same gas will be obtained byA. heating `NH_(4)NO_(2)`B. heating `NH_(4)NO_(3)`C. treating `H_(2)O_(2)` with `NaNO_(2)`D. treating `Ma_(3)N_(2)` with `H_(2)O` |
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Answer» Correct Answer - A `(NH_(4))_(2)Cr_(2)O_(7)overset("heat")(rarr)N_(2)+Cr_(2)O_(3)+4H_(2)O` `NH_(4)NO_(2)rarrN_(2)+2H_(2)O ("Same gas i.e., "N_(2))` |
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| 18. |
Iron `(+II)` is one of the most important oxidation states, and salts are called ferrous salts. Most of `Fe(+II)` salts are pale green and contain `[Fe(H_(2)O)_(6)]^(2+)` ion. `Fe(+II)` compounds are easily oxidised by air and so are difficult to obtain pure `Fe^(2+)` form many complexes like `K_(4)[Fe(CN)_(6)]` `K_(3)[Fe(CN)_(6)]` is used in the detection of `Fe^(2+)` ion with which it gives a deep blue colour. This colour is due to the formation ofA. `K_(2)Fe[Fe(CN)_(6)]`B. `Fe_(4)[Fe(Cn)_(6)]_(3)`C. `Fe[Fe(CN)_(6)]`D. `Fe_(3)[Fe(CN)_(6)]_(2)` |
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Answer» Correct Answer - D Conceptual |
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| 19. |
Iron `(+II)` is one of the most important oxidation states, and salts are called ferrous salts. Most of `Fe(+II)` salts are pale green and contain `[Fe(H_(2)O)_(6)]^(2+)` ion. `Fe(+II)` compounds are easily oxidised by air and so are difficult to obtain pure `Fe^(2+)` form many complexes like `K_(4)[Fe(CN)_(6)]` Anhydrous `FeCl_(2)` is made byA. heating Fe with dilute HClB. heating Fe with gaseous HClC. reacting Fe with conc. HClD. heating Fe with `Cl_(2)` gas |
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Answer» Correct Answer - B Conceptual |
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| 20. |
Iron `(+II)` is one of the most important oxidation states, and salts are called ferrous salts. Most of `Fe(+II)` salts are pale green and contain `[Fe(H_(2)O)_(6)]^(2+)` ion. `Fe(+II)` compounds are easily oxidised by air and so are difficult to obtain pure `Fe^(2+)` form many complexes like `K_(4)[Fe(CN)_(6)]` `FeSO_(4)` is used in brown ring test for nitrates and nitrites. In this test , a freshly prepared `FeSO_(4)` solution is mixed with solution containing `NO_(2)^(-)` or `NO_(2)^(-)` and the conc. `H_(2)SO_(4)` is run down the side of the test tube. If the mixture gets hot or is shaken. `I)` the brown colour disappear `II)` No is evolved `III)` a yellow solution of `Fe_(2)(SO_(4))_(3)` is formedA. I,II,III correctB. I,II correctC. II,III correctD. only I correct |
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Answer» Correct Answer - A Conceptual |
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| 21. |
Which of the following statements (s) is (are) not correct with reference to ferrous and ferric ionsA. `Fe^(3+)` gives brown colour solution with potassium ferricyanideB. `Fe^(2+)` gives red colour precipitate with potassium ferricyanideC. `Fe^(3+)` gives red colour solution with potassium sulphocyanide.D. `Fe^(2+)` gives brown colour solution with potassium sulphocyanide. |
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Answer» Correct Answer - D `Fe^(2+)` does not give brown colour with KCNS |
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| 22. |
`CuSO_(4)` solution reacts with excess of KCN solution to form:-A. `[Cu(CN)_(4)]^(2-)`B. `[Cu(CN)_(4)]^(3-)`C. `Cu(CN)_(2)`D. `Cu_(2)(CN)_(2)` |
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Answer» Correct Answer - B `2CuSO_(4)+10KCNrarr2K_(3)[Cu(CN)_(4)]+(CN)_(2)+2K_(2)SO_(4)` |
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| 23. |
Exess of KI reacts with `CuSO_(4)` solution and then `Na_(2)S_(2)O_(3)` solution is added to it. Which of the following statement is incorrect for this reaction ?A. Evolved `I_(2)` is reducedB. `CuI_(2)` is formedC. `Na_(2)S_(2)O_(3)` is oxidisedD. `Cu_(2)I_(2)` is formed |
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Answer» Correct Answer - B `2CuSO_(4)+4KI rarr2K_(2)SO_(4)+Cu_(2)I_(2)+I_(2)` `2Na_(2)S_(2)O_(3)+I_(2)rarr Na_(2)S_(4)O_(6)+2NaI,CuI_(2)` is not formed according to following reaction. `2CuI_(2)(` unstable) `rarrCu_(2)I_(2)+I_(2)` |
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| 24. |
A white percipitate of AgCl dissolves in excess of `I) NH_(3)(aq)" " II)Na_(2)S_(2)O_(3)" "III)NaCn`A. III onlyB. I,II,IIIC. I,IID. I only |
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Answer» Correct Answer - B due to formation of dissolved compl `underset((aq))(AgCl+NH_(3))rarrunderset(("soluble"))([Ag(NH_(3))_(2)]^(+)Cl^(-))` `AgCl+Na_(2)S_(2)O_(3)rarrAg_(2)(S_(2)O_(3))` `AgCl+NaCNrarrunderset(("soluble"))(Na[Ag(CN)_(2)])` |
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| 25. |
When `KMnO_(4)` solution is added to hot oxalic acid solution, the decolourisation is slow in the beginning but becomes instantaneous after some time. This is because.A. `Mn^(2+)` acts as auto catalystB. `CO_(2)` is formedC. Reaction is exothermicD. `MnO_(4)^(-)` catalyses the reaction |
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Answer» Correct Answer - A due to Autocatalyser of `Mn^(+2)` |
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| 26. |
When `KMnO_(4)` solution is added to hot oxalic acid solution the decoloursitation is slow in the beginning but becomes instantaneous after some time. This is becauseA. `Mn^(2+)` acts as auto catalystB. `CO_(2)` is formedC. reaction is exothermicD. `MnO_(4)^(-)` catalyses the reaction |
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Answer» Correct Answer - A `(NH_(4))_(2)Cr_(2)O_(7)overset(Delta)(rarr)Cr_(2)O_(3)` |
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| 27. |
When Cu powder is heated with `CuCl_(2)` solution, the compound obtained isA. `Cu[CuCl_(4)]`B. `Cu_(2)[CuCl_(4)]`C. `Cu_(2)O`D. `Cu_(2)Cl_(2)` |
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Answer» Correct Answer - D Cu reduces `CuCl_(2)` to `Cu_(2)Cl_(2)` |
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| 28. |
Copper `(II)` is estimated by the addition of the following reagentA. excess KCN solutionB. excess KI solutionC. excess `Na_(2)S_(2)O_(3)`D. excess aq. `NH_(3)` |
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Answer» Correct Answer - B `2CuSO_(4)+4KIrarrCu_(2)I_(2)+2K_(2)SO_(4)+I_(2)` |
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| 29. |
The color of B isA. BrownB. YellowC. BlackD. Blue |
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Answer» Correct Answer - A `Cu_(2)[Fe(CN)_(6)]darr` |
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| 30. |
`underset(("Acidified"))(KMnO_(4))+HCltoH_(2)O+X(g),X` is a:A. red liquidB. violet gasC. greenish yellow gasD. yellow-brown gas |
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Answer» Correct Answer - C `2KMnO_(4)+16HClrarr2KCl+2MnCl_(2)+8H_(2)O+5Cl_(2)` |
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| 31. |
`Cr_(2)O_(7)^(2-)underset(Y)overset(X)hArr2CrO_(4)^(2-),` X and Y are respectively.A. `X=OH^(-),Y=H^(+)`B. `X=H^(+),Y=OH^(-)`C. `X=OH^(-),Y=H_(2)O_(2)`D. `X=H_(2)O_(2),Y=OH^(-)` |
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Answer» Correct Answer - A `Cr_(2)O_(7)^(-2)underset(H^(+))overset(OH^(-))hArr 2CrO_(4)^(-2)` |
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| 32. |
Statement `1: FeCl_(2)` is a primary standard substance. Statement `2:` The weight of `FeCl_(2)` does not change with time by any means.A. Statement1 is True, Statement 2 is True, Statement2 is correct explanation for Statement 1B. Statement 1 is True, Statement 2 is True, Statement 2 is not a correct explanation for Statement 1C. Statement -1 is True, Statement -2 is FalseD. Statement -1 is False, statement -2 is True. |
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Answer» Correct Answer - A Primary standard solution means it will not change its concentration by Atmospheric conditions. |
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| 33. |
The oxidation number of Mn in the product of alkaline oxidative fusion of `MnO_(2)` is |
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Answer» Correct Answer - 6 `2MnO_(2)+4KOH+O_(2)rarr2K_(2)MnO_(4)+2H_(2)O` Oxidation number of Mn is `K_(2)MnO_(4)` is 6 `K_(2)MnO_(4),2+x-8=0" "x=6` |
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| 34. |
Choose the correct options ( true or false ) for the following statements. `i)` FeO is stable enough at room temperature. `ii) FeCl_(2)` on heating in air and in steam produces the same iron oxide. `iii)` The colour of `FeCl_(2)` depends upon the number of water of crystallization.A. T T FB. F T FC. F F TD. T F T |
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Answer» Correct Answer - C The colour of `FeCl_(2)` depends on water of crystallisation. |
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| 35. |
Among the following which is most stable ? `(1) underset((X))([Fe(CN)_(6)]^(3-))" and "underset((Y))([FeF_(6)]^(3-))` `(2) underset((S))([Fe(CN)_(6)]^(3-))" and "underset((T))([Fe(CN)_(6)]^(4-))` `(3) underset((P))([Cr(CN)_(6)]^(N-6))" and "underset((Q))([Cr(CN)_(6)]^(n-4))` Choose the correct codeA. `1-X,2-T,3-Q`B. `1-X,2-S,3-Q`C. `1-X,2-S,3-P`D. `1-Y,2-T,3-Q` |
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Answer» Correct Answer - C `CN^(-)gtF` ( higher the charge on the metal greater the stability . 6 coordinate complexes are more stable than four coordinated one. |
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| 36. |
Which one of the following compounds is not stable ?A. `PbCl_(2)`B. `PbI_(4)`C. `SnCl_(2)`D. `SnCl_(4)` |
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Answer» Correct Answer - B `Pb^(4+)` oxidizes `I^(-)` to `I_(2)` |
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| 37. |
The stable oxidation states of Mn areA. "+2,+3"B. "+2,+7"C. "+3,+7"D. "+3,+5" |
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Answer» Correct Answer - B Electronic configuration of `Mn` is `(Ar)3d^(5)4s^(2),` So stable oxidation state of Mn is `+2 & +7` |
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| 38. |
Chrome iron ore (x) was heated with dry `Na_(2)CO_(3)` in the presence of quick lime and air in a furnace. The mixture was extracted with water and filtered. The filtrate was yellow(A) which on adding conc. `H_(2)SO_(4)` turned to orange red. The solution was evaporated and cooled. The crystals of B were obtained. To the crystals in aqueous solution, `NH_(4)Cl` was added. On fractional crystallization, orange red crystals (C ) is formed. The correct statement isA. Dichromate ion is stable is basic mediumB. Dichromate is stable in acidic mediumC. Chromate is stable in acidic mediumD. Chromate undergoes hydrolysis to dichromate |
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Answer» Correct Answer - B `CrO_(4)^(2-)` is stable in basic medium. `Cr_(2)O_(7)^(2-)` is stable in acidic medium |
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| 39. |
Iron exhibits `+2 and +3` oxidation states. Which of the following statements about iron is incorrect?A. Ferrous oxide is more basic in nature then the ferric oxideB. Ferrous compounds are relatively more ionic than the corresponding ferric compoundsC. Ferrous compounds are less volatile than the corresponding ferric compoundsD. Ferrous compounds are more easily hydrolysed than the corresponding ferric com pounds. |
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Answer» Correct Answer - D `(d) Fe^(3+)` is easily hydrolysed than `Fe^(2+)` due to the more positive charge. |
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| 40. |
Chrome iron ore (x) was heated with dry `Na_(2)CO_(3)` in the presence of quick lime and air in a furnace. The mixture was extracted with water and filtered. The filtrate was yellow(A) which on adding conc. `H_(2)SO_(4)` turned to orange red. The solution was evaporated and cooled. The crystals of B were obtained. To the crystals in aqueous solution, `NH_(4)Cl` was added. On fractional crystallization, orange red crystals (C ) is formed. When alkali is added to B, the species formed isA. `Cr_(2)O_(7)^(2-)`B. `Cr^(3+)`C. `CrO_(4)^(2-)`D. `Cr^(4+)` |
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Answer» Correct Answer - C `Cr_(2)O_(7)^(2-)+2OH^(-)rarr2CrO_(4)^(2-)+H_(2)O` |
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| 41. |
The rusting of iron is formulated as `Fe_(2)O_(3)*xH_(2)O` which involves the formation of:A. `Fe_(2)O_(3)`B. `Fe(Oh)_(3)`C. `Fe(OH)_(2)`D. `Fe_(2)O_(3)+Fe(OH)_(3)` |
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Answer» Correct Answer - D due to formation of `Fe_(2)O_(3)+Fe(OH)_(3)` |
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| 42. |
`CuSO_(4).5H_(2)O overset(1000^(@)C)(rarr)underset(("solide")("gas"))(A+B)+O_(2)` `underset("bluish white")(CuSO_(4).H_(2)O)overset(x)(hArr)underset("white")(CuOS_(4))`hereA. `A=CuSO_(4)`B. `A=CuO`C. `B=SO_(2)`D. `X=230^(@)C` |
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Answer» Correct Answer - B,C,D `underset("Blue")(CuSO_(4).5H_(2)O)overset("exposes")(hArr)overset("Pale Blue")(CuSO_(4).)3H_(2)Ooverset("100^(@)C")(hArr) underset("bluish white")(CuSO_(4).H_(2)O)overset(230^(@)C)(hArr)underset("white")(CuSO_(4))underset(Delta)overset(720^(@)C")(hArr)CuO+SO_(2)+(1)/(2)O_(2)` Hence `A=CuO,B=SO_(2),X=230^(@)C` |
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| 43. |
In the following reaction sequence in aqueous solution, the species X,Y and Z, respectively `S_(2)O_(3)^(2-)overset(Ag^(+))(rarr)underset("clear solution")(X)overset(Ag^(+))(rarr)underset("white precipitate")(Y)overset("withtime")(rarr)underset(" black precipitate")(Z)`A. `[Ag(S_(2)O_(3))_(2)]^(3-),Ag_(2)S_(2)O_(3),Ag_(2)S`B. ` [Ag(S_(2)O_(3))_(3),Ag_(2)SO_(3),Ag_(2)S`C. `[Ag(SO_(3))_(2)]^(3-),Ag_(2)S_(2)O_(3),Ag`D. `[Ag(SO_(3))_(3)]^(3-),Ag_(2)SO_(4),Ag` |
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Answer» Correct Answer - A `Ag^(+)+S_(2)O_(3)^(2-)rarrunderset((X))([Ag(S_(2)O_(3))_(2)]^(3-))overset(Ag^(+))(rarr)(darr)overset("Withtime")(rarr)underset("balck (Z))(Ag_(2)S)` |
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| 44. |
Zinc carbonate is precipitated from zinc sulphate solution by the addition of:A. Sodium carbonateB. Calcium carbonateC. Sodium bicarbonateD. Sodium hydroxide `+` Sodium carbonate |
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Answer» Correct Answer - C Addition of `Na_(2)CO_(3)` gives zinc carbonate and zinc hydroxide . `NaHCO_(3)` is an acid salt. |
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| 45. |
Massicot isA. a yellow powder form of PbOB. a buff coloured crystalline form of PbOC. a yellow crystalline form of `PbO_(2)`D. a buff coloured powder of `PbO_(2)` |
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Answer» Correct Answer - A Yellow form of PbO is called Massicol |
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| 46. |
Metastannic Acid on heating givesA. `SnO`B. `Sn(OH)Cl`C. `SnO_(2)`D. `SnCl_(2)` |
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Answer» Correct Answer - C `H_(2)SnO_(3)overset(Delta)(rarr)SnO_(2)+H_(2)O` |
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| 47. |
Calomel `(H_(2)Cl_(2))` on reaction with ammonium hydroxide givesA. HgOB. `Hg_(2)O`C. `NH_(2)-Hg-Hg-Cl`D. `HgNH_(2)Cl` |
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Answer» Correct Answer - D `(d) Hg_(2)Cl_(2)+2NH_(4)OH rarr HgNH_(2)Cl+NH_(4)Cl+2H_(2)O` |
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| 48. |
In which reaction (s) blood red coloration is observed in product?A. `FeSO_(4)overset(H_(2)O_(2))(rarr).......overset("KSCN")(rarr)"product"`B. `Na_(2)S_(2)O_(3)overset("KSCN")(rarr)..........overset(Fe^(3+))(rarr)"product"`C. `NH_(4)SCNoverset("Ferric alum")(rarr)"product"`D. `NO_(2)^(-)overset("Thiourea")(rarr).......overset(Fe^(3+))(rarr)"product"` |
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Answer» Correct Answer - A,B,C,D `Fe(SCN)_(3)` is blood red coloured compound |
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| 49. |
Which of the following can act as a good mordant ?A. `SnCl_(4)`B. `SnCl_(2)`C. `PbCl_(2)`D. `PbI_(4)` |
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Answer» Correct Answer - A `SnCl_(4)` hydrolysis to `Sn(OH_(4)` and adsorbs the dye |
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| 50. |
Which of the following liberate `Cl_(2)` when heated with conc. HCl ?A. `KMnO_(4)`B. `MnO_(2)`C. `SnO_(2)`D. `PbO_(2)` |
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Answer» Correct Answer - A,B,D `SnO_(2)` does not oxidize `Cl^(-)` to `Cl_(2)` |
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