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201.

A mixture when rubbed with dilute acid smells like vinegar. It contains:A. sulphiteB. nitrateC. nitrileD. acetate

Answer» Correct Answer - D
202.

When `PbCO_(3)` reacts with dil. HCl (or) dil. `H_(2)SO_(4)` give `CO_(2)` for a moment. Then the reaction slows down. It is because ofA. `PbCO_(3)` does not reacts with dil. HCl (or) `H_(2)SO_(4)` vigorously.B. Formation of protective layer of `PbCl_(2)` (or) `PbSO_(4)`C. Dil. HCl (or) `H_(2)SO_(4)` is oxidising `PbSO_(4)`D. None of the above.

Answer» Correct Answer - 2
203.

Which anion does not liberate any gas with dilute as well as conc. `H_(2)SO_(4)`.A. I GroupB. II GroupC. III GroupD. IV Group

Answer» Correct Answer - C
204.

Salt`(A)` on heating gives a colourless neutral gas which supports combustion. From the aforesaid, flow diagram, answer the following questions. The compound `(A)` contains the following acid radical.A. `NO_(2)^(-)`B. `NO_(3)^(-)`C. `Br^(-)`D. `SO_(3)^(2-)`

Answer» Correct Answer - B
`NO_(3)^(-)` and `NO_(2)^(-)` both give brown ring test and reduction of `NO_(3)^(-)` and `NO_(2)^(-)` both give ammonia which with dilute `HCl` gives dense white fumes.
if `NH_(4)NO_(3)overset(Delta)toN_(2)O+2H_(2)O,N_(2)O` supports the combustion
but `NH_(4)NO_(2)overset(Delta)toN_(2)+2H_(2)O`Nitrogen does not supports combustion.
Hence, the anion is `NO_(3)^(-)`.
205.

Which of the following is formed when `CO_(2)` gas is passed through an aqueous solution of sodium chromate ?A. `Cr(OH)_(3)` is precipitatedB. Orange solution of `Na_(2)Cr_(2)O_(7)` is formedC. Yellow solution of `Cr_(2)(CO_(3))_(2)` is formedD. No reaction.

Answer» Correct Answer - 2
`CO_(2)` makes the solution acidic. Under acidic conditions, `Na_(2)CrO_(4)` is converted into `Na_(2)Cr_(2)O_(7)`
206.

A metallic chloride when diluted with water gives precipitate . It indicates the presence ofA. AlB. BiC. SbD. Zn

Answer» Correct Answer - B::C
207.

`Fe^(3+)overset(SCN^(-) ("excess"))rarr "Blood red (A)" overset(F^(-)("excess"))rarr "Colourless (B)"` Identify A and B. (i) Write IUPAC name of A and B. (ii) Find out spin only magnetic moment of B.

Answer» Correct Answer - `(5.92 BM)`
208.

`NH_(4)SCN` can be used to test one or more out of `Fe^(3+) , Co^(2+) , Cu^(2+)`:A. `Fe^(3+)` onlyB. `Co^(2+), Cu^(2+)` onlyC. `Fe^(3+), Cu^(2+)` onlyD. All

Answer» Correct Answer - D
`Fe^(3+) +3SCN^(-) to Fe(SCN)_(3)` (deep red colouration)
`Co^(2+) +4SCN^(-) overset("amyl alcohol") to [Co(SCN)_(4)]^(2-)` (blue colouration)
`Cu^(2+) + 2SCN^(-) to Cu(SCN)_(2) darr ("black"),2Cu(SCN)_(2) to 2CuSCN darr ("white")+(SCN)_(2)`
209.

Which of the following substances are soluble in concentrated `HNO_(3)`A. `BaSO_(4)`B. `CuS`C. `PbS`D. `Bi_(2)S_(3)`

Answer» Correct Answer - B,C,D
210.

White precipitate of `PbSO_(4)` gets dissolved in:A. concentrated `H_(2)SO_(4)` on heatingB. concentrated `NaOH`C. `(NH_(4))_(2)CO_(3)`D. Dilute `HNO_(3)`

Answer» Correct Answer - A,B
(A)`PbSO_(4)darr +H_(2)SO_(4)` (hot and concentrated) `to Pb^(2+)+2HSO_(4)^(-)`(soluble)
(B)It dissolves forming `Na_(2)[Pb (OH)_(4)]` soluble complex.
211.

Original solution of salt or mixture should not be prepared in concentrated `HNO_(3)` because it:A. is highly corrosiveB. oxidises `H_(2)S` to `S` in `II^(nd)` group.C. undergoes disproportionation reactionD. converts sulphide of `Ba, Sr` and `Pb` into insoluble sulphates

Answer» Correct Answer - B,D
(B)`2HNO_(3)to 2NO_(2)+H_(2)O+[O],H_(2)S+[O]toH_(2)O+S darr`
(D)`2HNO_(3)to 2NO_(2)+H_(2)O+[O],PbS+[O]to PbSO_(4) darr`
212.

In step-III if `Pb(CH_(3)CO O)_(2)` is added without acidifying the solution with `CH_(3)CO OH` then possibel product may be :A. `PbCrO_(4)`B. `Na_(2)Cr_(2)O_(7)`C. `Na_(2)CrO_(4)`D. `Na_(2)PbO_(2)`

Answer» Correct Answer - A::D
213.

What happens when ? (a)To a `Zn^(2+)` ions solution faintly acidified with `2M` acetic acid, `0.1 mL` of `0.25 M CuSO_(4)` solution and `2 mL` of ammonium tetrathiocyanatomercurate `(II)` reagents is added. (b) The above test is performed in absence of `CuSO_(4)` solution.

Answer» Correct Answer - (a)violet (or blackish-purple ) precipitate consisting of `Zn[Hg(SCN)_(4)]` and `Cu[Hg(SCN)_(4)]` is formed.
(b)`Zn^(2+) + [Hg(SCN)_(4)]^(2-) to Zn[Hg(SCN)_(4)]darr` (white)
214.

Gas (B) on passing through cadmium acetate solution will give :A. Black pptB. Yellow pptC. Orange pptD. White ppt

Answer» Correct Answer - B
215.

The missing product in the reaction `Mg^(2+)+HPO_(4)^(2-)+NH_(4)OH rarr ? +H_(2)O` is `:`A. `Mg(NH_(4))PO_(4)`B. `Mg_(3)(PO_(4))_(2)`C. `MgPO_(4)`D. None of these

Answer» Correct Answer - A
216.

Which of the following combines with `Fe(II)` ions to form a brown complex ?A. `N_(2)O`B. `NO`C. `N_(2)O_(3)`D. `N_(2)O_(4)`

Answer» Correct Answer - B
217.

In the reaction sequence: `CrO_(2)Cl_(2)overset(NaOH) to A overset(dil. H_(2)SO_(4)) to B overset (NaOH) to C overset(AgNO_(3)) to D` Identify `[A]` to `[D]`.

Answer» Correct Answer - A=`Na_(2)CrO_(4)`, B=`Na_(2)Cr_(2)O_(7)` , C=`Na_(2)CrO_(4)` , D=`Ag_(2)CrO_(4)`
`CrO_(2)Cl_(2)+4NaOH to Na_(2)CrO_(4) (A)+2NaCl + 2H_(2)O`
`Na_(2)CrO_(4)+H_(2)SO_(4) to 2Na_(2)Cr_(2)O_(7)(B)+Na_(2)SO_(4)+H_(2)O`
`Na_(2)Cr_(2)O_(7) +2Na_(2)CrO_(4) (C )+H_(2)O`
`Na_(2)CrO_(4) +2AgNO_(3) to Ag_(2)CrO_(4) (D) +2NaNO_(3)`
218.

Aqueous `ZnSO_(4)` treated with `Na_(2)CO_(3)//H_(2)O` produces A which when heated forms B which further treated with cobalt nitrate and warmed C is formed. A,B and C are respectively.A. `ZnCO_(3), Zn` and `CoO`B. `ZnO,Zn` and `CoZnO_(2)`C. `ZnCO_(3).3Zn(OH)_(2),ZnO` and `CoZnO_(2) ` respectivelyD. `ZnCO_(3), ZnO,CoO`

Answer» Correct Answer - C
219.

Gas (B) and (E ) are respectively :A. `H_(2)S, NH_(3)`B. `H_(2)S, SO_(2)`C. `SO_(2), H_(2)S`D. `H_(2)S, CO_(2)`

Answer» Correct Answer - B
220.

Why in cobalt nitrate test for aluminium salts, excess of cobalt nitrate should not be added ?

Answer» Correct Answer - This gives black cobalt oxide, `Co_(3)O_(4)`, upon ignition and this mask the colour of thernad blue `(CoAl_(2)O_(4))`.
221.

Select the only correct option.A. (I) (i) (P)B. (II) (ii) (Q)C. (I) (ii) (S)D. (II) (iii) (Q)

Answer» Correct Answer - A
222.

If a dilute solution of aqueous `NH_(3)` is saturated with `H_(2)S` then the product formed is :A. `(NH_(4))_(2)S`B. `NH_(4)HS`C. `(NH_(4))_(2)S_(x)`D. `NH_(4)OH+S`

Answer» Correct Answer - B
223.

Which of the following statements is /are incorrect?A. A filter paper moistened with cadmium acetate solution turn yellow, when brought in contact with `H_(2)S` gas.B. Both carbonate ions as well as bicarbonate ions in the solutions, give reddish-brown precipitate with mercury `(II)` chloride.C. Sulphites in presence of zinc, reacts with dilute `H_(2)SO_(4)` to liberate `SO_(3)` gas.D. A filter paper moistened with `KIO_(3)` and starch turns blue in contact with `SO_(2)` vapours.

Answer» Correct Answer - B,C
(A)`Cd^(2+)(aq)+H_(2)S(g)toCdSdarr("yellow ")+2H^(+)(aq)`
(B)`Co_(3)^(2-)+4Hg^(2+)+3H_(2)O to Hg_(4)O_(3)CO_(3)darr ("reddish-brown")+6H^(+)`
`HCO_(3)^(-) (aq)` does not give precipitate.
( C)`SO_(3)^(2-)+3Zn+8H^(+) to H_(2)S uarr 3Zn^(2-)+3H_(2)O`
(D )`5SO_(2)+2IO_(3)^(-)+4H_(2)OtoI_(2)+5SO_(4)^(2-)+8H^(+)`
224.

(i)A blue coloured compound `(A)` on heating gives two product `(B)` & `( C)`. (ii)A metal `(D)` is deposited on passing hydrogen through heated `(B)`. (iii)The solution of `(B)` in `HCl` on treatment with the `[Fe(CN)_(6)]^(4-)` gives a chocolate brown coloured precipitate of compound `(E)`. (iv)`(C )` turns lime water milky which disappears on continuous passage of `(C )` forming a compound `(F)`. Identigfy `(A)` to `(F)` and give chemical equations for the reactions at step (i) to (iv).

Answer» Correct Answer - A=`CuCO_(3)`, B=`CuO` , C=`CO_(2)` , D=`Cu` , E=`Cu_(2)[Fe(CN)_(6)]`,F=`Ca(HCO_(3))_(2)`
(i)`CuCO_(3)(A) overset(Delta)toCuO (B)+CO_(2) (C )`, (ii)`CuO (B) +H_(2) overset(Delta)toCudarr(D)+H_(2)O`
(iii)`2Cu^(2+)+[Fe(CN)_(6)]^(4-) to 2Cu_(2) [Fe(CN)_(6)]darr`(chocolate brown) `(E)`
(iv)`CO_(2)+Ca(OH)_(2)toCaCO_(3)darr+H_(2)O , CaCO_(3)+H_(2)O+CO_(2)toCa(HCO_(3))_(2)`(soluble)
225.

Select the only incorrect option.A. (III) (i) (P)B. (I) (ii) (Q)C. (IV) (i) (R )D. (IV) (ii) (Q)

Answer» Correct Answer - B
226.

A white substance `(A)` reacts with dilute `H_(2)SO_(4)` to produce a colourless gas `(B)` and a colourless solution `( C)`.The reaction between `(B)` and acidified `K_(2)Cr_(2)O_(7)` solution produces a green solution and a slightly coloured precipitate `(D)`.The substance `(D)` burns in air to produce a gas `(E)` which reacts with `(B)` to yield `(D)` and a colourless liquid. Anhydrous copper sulphate is turned blue on addition of this colouless liquid.Addition of aqueous `NH_(3)` or `NaOH` to `( C)` produces first a white precipitate which dissolves in the excess of the respective reagent to produce a clear solution in each case. Identify `(A),(B),( C),(D)` and `(E)`.

Answer» Correct Answer - (A)`ZnS` ; (B)`H_(2)S` ; (C )`ZnSO_(4)` ; (D)`S` ; (E)`SO_(2)`
`ZnS+H_(2)SO_(4)to ZnSO_(4) + H_(2)S`
`Cr_(2)O_(7)^(2-) + 3H_(2)S+8H^(+) to 2Cr^(3+) ("green solution")+3S darr +7H_(2)O`
`S+O_(2) to SO_(2) , 2H_(2)S +SO_(2) to 2H_(2)O+3S`
`Zn^(2+)+2OH^(-) toZn(OH)_(2) darr` (white)
`Zn^(2+)+2NH_(3)+ H_(2)O hArrZn(OH)_(2) darr("white")+NH_(4)^(+)`
`Zn(OH)_(2) darr +4NH_(3) hArr [Zn(NH_(3))_(4)]^(2+) +2OH^(-)`
227.

(i) An aqueous solution of a compound (A) is acidic towards litmus and (A) sublimes at about `300^(@)C`. (ii) (A) on treatment with an excess of `NH_(4)SCN` gives a red coloured compound (B) and on treatment with a solution of `K_(4)[Fe(CN)_(6)]` gives a blue coloured compound (C). (iii) (A) on heating with excess of `K_(2)Cr_(2)O_(7)` in the presence of concentrated `H_(2)SO_(4)` evolves deep red vapours of (D). (iv) On passing the vapour of (D) into a solution of NaOH and then adding the solution of acetic acid and lead acetate, a yellow precipitate of compound (E) is obtained. Identify (A) to (E) and give chemical equations for the reactions.

Answer» Correct Answer - A=`FeCl_(3)`, B=`Fe(SCN)_(3)` , C=`Fe_(4)[Fe(CN)_(6)]_(3)` , D=`CrO_(2)Cl_(2)` , E=`PbCrO_(4)`
(i)`FeCl_(3)+3H_(2)O to Fe(OH)_(3)darr` (reddish brown) +`3HCl`,so solution is acidic in nature.
(ii)`Fe^(3+) +3SCN^(-) to Fe(SCN)_(3)` (red colouration)
`4Fe^(3+) +3[Fe(CN)_(6)]^(4-) toFe_(4)[Fe(CN)_(6)]_(3)`(Prussian blue).
(iii)`Cr_(2)O_(7)^(2-)+4Cl^(-) 6H^(+) to 2CrO_(2)Cl_(2) uarr` (deep red) +`3H_(2)O`
(iv)`CrO_(2)Cl_(2)uarr+4OH^(-)toCrO_(4)^(2-) + 2Cl^(-)+2H_(2)O`
`Pb^(2+) +CrO_(4)^(2-) to PbCrO_(4) darr` (yellow)
228.

Which of the following statements is incorrect ?A. A filter paper moistened with cadmium acetate solution turns yellow, when brought in contact with `H_(2)S` gas.B. Both carbonate ions as well as bicarbonate ions in the solubtions, give reddish`-` brown precipitate with mercury `(II)` chloride.C. Sulphites in presence of zinc, reacts with dilute `H_(2)SO_(4)` to liberate `H_(2)S` gas.D. A filter paper moistened with `KIO_(3)` and starch turns blue in contact with `SO_(2)` vapours.

Answer» Correct Answer - 2
`(1)Cd^(2+)(aq)+H_(2)S(g)rarrCdSdarr("yellow")+2H^(+)(aq)`
`(2)Co_(3)^(2-)+4Hg^(2+)+3H_(2)OrarrHg_(4)O_(3)CO_(3)darr("reddish-brown")+6H^(+)`
`HCO_(3)^(-)(aq)` down not give precipitate.
`(3)SO_(3)^(2-)+3Zn+8H^(+)rarrH_(2)Suarr+3Zn^(2+)+3H_(2)O`
`(4)5SO_(2)+2IO_(3)^(-)+4H_(2)OrarrI_(2)+5SO_(4)^(2-)+8H^(-)`
229.

A mixture of two salts was treated as follows. (i)The mixture was heated with precipitated `MnO_(2)` and concentrated `H_(2)SO_(4)` when a yellowish green gas was liberated. (ii)The mixture on heating with `NaOH` solution gave a gas which turned red litmus blue. (iii)Its solution in water gave red colouration with dimethylglyoxime in alkaline solution and white precipitate with `K_(4)[Fe(CN)_(6)]` in absence of air. (iv)The mixture was boiled with `KOH` and the liberated gas was bubbled through an alkaline solution of `K_(2)HgI_(4)` to give a brown precipitate. Identify the ions present in the mixture.

Answer» Correct Answer - The given unknown mixture contains `NH_(4)^(+),Fe^(2+)` and `Cl^(-)` ions or `NH_(4)Cl` and `FeCl_(2)`
230.

How do we differentiate between `CO_(3)^(2-)` and `SO_(3)^(2-)` in dilute `H_(2)OSO_(4)` group ? ( Note `:` These are sodium salts ?A. By passing gas liberated with dilute `H_(2)SO_(4)` through lime water.B. By passing gas liberated with dilute `H_(2)SO_(4)` through acidified `K_(2)Cr_(2)O_(7)` solution.C. By the addidtion of lead acetate solution in their aqueous solutions .D. By the addition of silver nitrate solution in their aqueous solutions.

Answer» Correct Answer - 2
`(1)CO_(3)^(2-)+2H^(+)rarrCO_(2)+H_(2)O" ",Ca(OH)_(2)+CO_(2)rarrCaCO_(3) darr ("white")+H_(2)O`
`CaCO_(3)+CO_(2)+H_(2)OrarrCa(HCO_(3))_(2)("soluble")`
`SO_(3)^(2-)+2H^(+)rarrSO_(2)+H_(2)O,Ca(OH)_(2)+SO_(2)rarr CaSO_(3)darr("white")+H_(2)O`
`CaSO_(3)+H_(2)O+SO_(2)rarrCa(HSO_(3))_(2)("soluble")`.
`(2)CO_(3)^(2-)+2H^(+)rarrCO_(2)+H_(2)O,Cr_(2)O_(7)^(2-)+H^(+)+CO_(2)rarr"No reaction"`
`SO_(3)^(2-)+2H^(+)rarrSO_(2)+H_(2)O,Cr_(2)O_(7)^(2-)+2H^(+)+3SO_(2)rarr2Cr^(3+)("green solution")+3SO_(4)^(2-)+H_(2)O`
`(3)Pb^(2+)+OS_(3)^(2-)rarrPbSO_(3)darr("white"),2Pb^(2+)+2CO_(3)^(2-)+H_(2)Orarrubrace(Pb(OH)_(2)darr+PbCO_(3)darr)_("while")+CO_(2)`
`(4) 2Ag^(+)+CO_(3)^(2-)rarrAg_(2)CO_(3)darr("white")" "," "2Ag^(+)+SO_(3)^(2-)rarrAg_(2)SO_(3)darr("white")`
231.

Ferric alum gives deep red colour with `NH_(4)SCN` due to the formation of `:`A. `Al(SCN)_(3)`B. `[Fe(SCN)_(3)]^(-)`C. `Fe(SCN)_(3)`D. none of these

Answer» Correct Answer - C
232.

A white sodium salt dissolves in water to give a solution which is neutral to litmus.When silver nitrate solution is added to the solution, a white precipitate is obtained which does not dissolve in dilute `HNO_(3)`.The anion isA. `CO_(3)^(2-)`B. `Cl^(-)`C. `SO_(3)^(2-)`D. `S^(2-)`

Answer» Correct Answer - B
`NaCl+AgNO_(3)toAgCl darr("white")+NaNO_(3),Ag_(2)S darr` (black)
`Ag_(2)CO_(3)` and `Ag_(2)SO_(3)` dissolves in dilute `HNO_(3)` liberating `CO_(2)` and `SO_(2)` respectively.
Both `Ag_(2)CO_(3)` and `Ag_(2)SO_(3)` are white.`AgCl` is white but insoluble in dilute `HNO_(3)``NaCl` solution is netural to litmus as it is a salt of strong acid and strong base.
233.

All nitrates on heating with conc. `H_(2)SO_(4)` in presence of paper pellet evolve `NO_(2)` gas. The function of the paper pellet is `:`A. reduce `HNO_(3)` to `N_(2)`B. to reduce `HNO_(3)` to `NO`C. to reduce `HNO_(3)` to `NO_(2)`D. to reduce `HNO_(3)` to `NH_(3)`

Answer» Correct Answer - 3
`2NO_(3)^(-)+H_(2)SO_(4)+CrarrrH_(2)CO_(3)+2NO_(2)+SO_(4)^(2-)`
234.

A salt gives violet vapours when treated with conc. `H_(2)SO_(4)`, it contains ?A. `Cl^(-)`B. `I^(-)`C. `Br^(-)`D. `NO_(3)^(-)`

Answer» Correct Answer - 2
235.

Ammonium molybdate test is used for the estimation of:A. `PO_(4)^(3-)`B. `Mg^(2+)`C. `As_(4)^(3-)`D. `CH_(3)COO^(-)`

Answer» Correct Answer - A,C
236.

Match the List -I (containing anions ) with List -II (containing reagent used in testing ) using the codes as given below in the column. `{:("List"-I,,"List"-II),(("anions"),,("reagents")),((a)S^(2-),,(p)"Barium chloride solution in presence of HCl"),((b)NO_(3)^(-),,(q)"Sodium nitroprusside"),((c)I^(-),,(r)"chlorine water and chloroform"),((d)SO_(4)^(2-),,(s)"iron"(II)"sulphate solution and conc."H_(2)SOS_(4)):}` Code `:`A. `{:(,"(a)","(b)","(c)","(d)"),(,"(q)","(s)","(r)","(p)"):}`B. `{:(,"(a)","(b)","(c)","(d)"),(,"(p)","(s)","(r)","(q)"):}`C. `{:(,"(a)","(b)","(c)","(d)"),(,"(q)","(p)","(r)","(s)"):}`D. `{:(,"(a)","(b)","(c)","(d)"),(,"(p)","(q)","(r)","(s)"):}`

Answer» Correct Answer - 1
`(a)" "[Fe(CN)_(5)NO]^(2-)+S^(2-)rarr[Fe(CN)_(5)NO]^(4-)("purple colouration")`
`S^(2+)+BaCl_(2)rarr"No precipitate".`
`(b)" "2NO_(3)^(-)+4H_(2)SO_(4)+6Fe^(2+)rarr6Fe^(3+)+2NOuarr+4SO_(4)^(2-)+4H_(2)O`
`[Fe(H_(2)O)_(6)]^(2+)+NOrarrunderset(("Brown complex"))([Fe(H_(2)O)_(5)NO]^(2+)+H_(2)O)`
`(c )" "2I^(-)+CL_(2)+I_(2)+2Cl^(-)`
`" "I_(2)+C CI_(4)rarrI_(2)` dissolves forming a violet solution.
`(d)" "Ba^(2+)+SO_(4)^(2-)rarrBaSO_(4)darr("white")`
`HCl` removes the impurities of `S^(2-),I^(-)` and `NO_(3)^(-)` and white precipitate of `BaSO_(4)` is thus obtained.
237.

When `HNO_(3)` is added to sodium ferrocyanide, which of the following observation is observed ?A. `NaFe[Fe(CN)_(6)]` is produced.B. `Fe_(4)[Fe(CN)_(6)]_(3)` is formed.C. `Fe_(3)[Fe(CN)_(6)]_(2)` is formed.D. `Na_(2)[Fe(CN)_(5)(NO)^(+)]^(2-)` is formed.

Answer» Correct Answer - D
`[Fe(CN)_(6)]^(4-)+NO_(3)^(-)+4H^(+)to[Fe(CN)_(5)(NO)]^(2-)+NH_(4)^(+)+CO_(2)`
238.

What product is formed by mixing the solution of `K_4 [Fe (CN)_6]` with the solution of `FeCl_2`?A. Ferro ferricyanideB. Ferric ferrocyanideC. Ferric ferricyanideD. None

Answer» Correct Answer - D
239.

NiS is separated from ZnS by treating withA. NaOHB. conc. HClC. yellow ammonium sulphideD. aqua regia

Answer» Correct Answer - 2
In the sulphides of IV group,
NiS is black and insoluble in conc. HCl white ZnS is soluble in conc. HCl.
240.

Ammonia forms the complex `[Cu(NH_3)_4]^(2+)` with copper ions in alkaline solution but not in acid solution. The reasons for it is:A. In alkaline solution insoluble `Cu(OH)_(2)` is precipitated which is soluble in excess of any alkaliB. `Cu(OH)_(2)` is amphotericC. In acidic solution hydration protects `Cu^(2+)` ionD. In acid solution proton coordinates with `NH_(3)` forming `NH_(4)^(+)` ion and `NH_(3)` is not available

Answer» Correct Answer - D
241.

Which of the following salt gives green colour mass in cobalt nitrate charcoal cavity test ?A. Al saltsB. Zn saltsC. Copper saltsD. Alumns

Answer» Correct Answer - B
242.

A salt gives white residue in charcoal cavity test but in cobalt nitrate test it gives pink mass. It represents :A. `Zn^(+2)`B. `Al^(+3)`C. `Mg^(+2)`D. `PO_(4)^(-3)`

Answer» Correct Answer - C
243.

Each of these are added to a mixture of aqueous solutions of iodide and `CHCl_(3)` separately. Which will give a positive test for iodine when the solution are vigorously mixed ?A. NaCl solutionB. NaBr solutionC. Chlorine waterD. Bromine water

Answer» Correct Answer - C::D
244.

Which of the following anions are identified by dil. HCl :A. `NO_(2)^(-),NO_(3)^(-),CO_(3)^(2-)`B. `NO_(2)^(-),NO_(3)^(-),SO_(3)^(2-)`C. `S^(2-),SO_(3)^(2-),NO_(2)^(-)`D. `CH_(3)CO O^(-),I^(-),CO_(3)^(2-)`

Answer» Correct Answer - C
245.

a=difference in the oxidation number of Cl in the product X and product Y, respectively b= total number of atom in X and Y c=total number of lone pair in X then calculate a+b+c = ?

Answer» Correct Answer - 14 (a=1, b=7, c=6)
246.

In the test for iodine, `I_(2)` is treated with sodium thiosulphate `(Na_(2)S_(2)O_(3))` : `Na_(2)S_(2)O_(3)+I_(2) to NaI +..`A. `Na_(2)S_(4)O_(6)`B. `Na_(2)SO_(4)`C. `Na_(2)S`D. `Na_(3)ISO_(4)`

Answer» Correct Answer - A
247.

Which of the following metal carbonates liberate. `CO_(2)(g)` on heating :A. `Na_(2)CO_(3)`B. `K_(2)CO_(3)`C. `Rb_(2)CO_(3)`D. `Ag_(2)CO_(3)`

Answer» Correct Answer - D
248.

`Na_(2)CO_(3),NaCl, NaNO_(2),Na_(2)SO_(3),NaBr,CH_(3)CO O Na` are separately treated with `AgNO_(3)` solution. In how many cases white precipitate is/are obtained.

Answer» Correct Answer - 5 (All except NaBr)
249.

Which of the following anion behaves in a different manner than other on heating with conc. `H_(2)SO_(4)` ?A. `Cl^(-)`B. `I^(-)`C. `Br^(-)`D. All behave in a similar manner

Answer» Correct Answer - A
250.

Two inorganic compounds A and B were heated in a dry test tube. A evolved a colourless gas which turned lead acetate paper black and B evolved a gas which turned lime water milky. The anions in A and B respectively are :A. `SO_(3)^(2-), CO_(3)^(2-)`B. `S^(2-), CO_(3)^(2-)`C. `PO_(4)^(3-), HSO_(3)^(-)`D. `S^(2-), NO_(3)^(-)`

Answer» Correct Answer - B