94420 + Interview Questions in Chemistry in Class 12

1.	{:(NaH_(2)PO_(4) overset( gt 240^(@)C)rarrunderset("Sodium trimetaphosphate")((NaPO_(3))_(3))overset(625^(@)C) rarrunderset("(liquid melt)")(NaPO_(3))),("rapid"darr"cooling"),("D(glass)"):} Compound (D) is known as :
Answer» MICROCOSMIC salt Graham's salt Reimann's salt Switzer's salt Answer :B

Discussion

2.	NaHC_(2)O_(4) is 0.1 M when neutralised with NaOH. Hence, it is ...... when oxidised with MnO_(4-)//H^(+) .
Answer» Solution : `NaHC_(2)O_(4) to n=2`(as a REDUCING agent) So, `0.1xx2=0.2N NaHC_(2)O_(4)` as a RA.

Discussion

3.	NaH crystallizes in the same structure as that of NaCl. The edge length of the cubic unit cell of NaH is 4.88 Å. (a) Calculate the ionic radius of H^(–), provided the ionic radius of Na+ is 0.95 Å. (b) Calculate the density of NaH.
Answer» ANSWER :1.49 Å,B1.37 G/`CM^(3)`

Discussion

4.	NaCN is sometimes added in the front loatation process as a depressant when ZnS and PbS minerals are expected because
Answer» `Pb(CN)_(2)` is precipitated while no effect on ZnS ZnS forms SOLUBLE complex `Na_(2) Zn(CN)_(4)]` while Phs COMES out with froth PbS forms soluble complex `Na_(2) [Pb(CN)_(4)]` while ZnS comes out with froth NaCN is never added in froth floatation process Solution :In the CONCENTRATION of Galena ore NaCN is added as depresent for Zns, NaCN forms layer of Zinc complex `Na_(2)[Zn(CN)_(4)]` on the surface of ZnS and prevent it from the formation of froth and Pbs forms froth.

Discussion

5.	NaClO_(3) is obtained by reacting Cl_(2) and
Answer» COLD dil. NaOH HOT conc. NaOH cold `Na_(2)O_(2)` hot `Na_(2)O_(2)` Answer :B

Discussion

6.	NaCN is added in froth floation process process with ZnS and PbS minerals because
Answer» `Pb(CN)_2` is precipitated while no effect on ZnS ZnS forms soluble complex while PbS forms froth it ACTS as a depressant NaCN is never ADDED in froth FLOATATION process. Solution :`NaCN` acts as a depressant when `ZnS, PbS` are present in the mineral. ZnS forms soluble complex `Na_(2)[ZN(CN)_(4)]` and PbS forms froth.

Discussion

7.	NaClO_(3) is used evenis spacecrafts to produce O_(2) . Thedaily consumptionfo pure O_(2)by a person is 492 L atatm , 300k .Howmuchamountof NaClO_(3),in gramsis requiredto produceO_(2)for thedailyconsumptionof a person at 1 atm 300K ?_________. NaClO_(3)(s) +Fe(s) to O_(2)(g) +NaCl_(s) +FeO(s) R = 0.082L atm mol^(-) K^(-1)
Answer» 21.3 1115 2130 4260 Answer :C

Discussion

8.	NaClO solution reacts with H_(2)SO_(3) as, NaClO+H_(2)SO_(3)rarr NaCl + H_(2)SO_(4). A solution of NaClO used in the above reaction contained 15g of NaClO per litre. The normality of the solution would be
Answer» `0.8` `0.6` `0.2` `0.4` Solution :`N=(W XX 1000)/(eq.wt. xx "VOLUME in ml.") =0.4 N`.

Discussion

9.	NaCl, NaBr, Nal mixture on adding conc. H_(2)SO_(4) gives gases respectively
Answer» HCL, `Br_(2), I_(2)`<BR>HCl, HBR, HI `Cl_(2), Br_(2), I_(2)` HCl, HBr, `I_(2)` Answer :A

Discussion

10.	NaCl ,NaBr , NaI mixtureon adding conc. H_2SO_4 gives gases respectively
Answer» `HCl . HBr. HI` `Cl_2 , Br_2 , I_2` `HCl, Br_2, I_2` None ANSWER :C

Discussion

11.	NaCl, NaBr and NaI mixture on heating with conc. H_2 SO_4 gives gases respectively.
Answer» HCl,`Br_(2),I_(2)` HCl,HBr,HI `Cl_(2),Br_(2),I_(2)` NONE SOLUTION :`NaCl+H_(2)SO_(4) OVERSET(DELTA)toNaHSO_(4) +HCl uarr` `HCl +H_(2)SO_(4) overset(Delta)to` No REACTION `NaBr +H_(2)SO_(4) overset(Delta)to NaHSO_(4)+HBr` `2HBr+H_(2)SO_(4) overset(Delta)to Br_(2)uarr+SO_(2)+2H_(2)O` `NaI +H_(2)SO_(4)overset(Delta)to NaHSO_(4)+HI` `2HI+H_(2)SO_(4)overset(Delta)to I_(2) uarr+SO_(2)+2H_(2)O`.

Discussion

12.	NaCl + K_(2)Cr_(2)O_(7)+H_(2)SO_(4) rarr NA_(2)SO_(4) + K_(2) SO_(4) +H_(2)O +X The oxidation state chromium in the product X
Answer» `+5` `+6` `+7` `+8` Solution :`4NaCl + K_(2) Cr_(2) O_(7) + 3H_(2) SO_(4) rarr 2Na_(2) SO_(4)+K_(2)SO_(4) + 3H_(2)O + 2CrO_(2) Cl_(2)` THUS X is `CrO_(2) Cl_(2)` chromyl chloride `:. ` O.N. of Cr is ` +6`

Discussion

13.	NaCl is doped with 2xx10^(-3) mole % of SrCl_(2). The concentration of cation vacancies is
Answer» `12.04xx10^(20)` per mole `3.01xx10^(18)` per mole `6.02xx10^(18)` per mole `12.04xx10^(18)` per mole Solution :The ADDITION of one `Sr^(2+)` REPLACES `2Na^(+)` and one cationic vacancy is created No. of cationic vacancy `=2xx10^(-3)` mole % of NaCl `=(2xx10^(-3))/(100) mol^(-1)` of NaCl `=2xx10^(-5)xx6.02xx10^(23)mol^(-1)` `=12.04xx10^(18)mol^(-1)` of NaCl `=2xx10^(-5)xx6.02xx10^(23)mol^(-1)` `=12.04xx10^(18)mol^(-1)` of NaCl.

Discussion

14.	NaCZ is doped with 2 xx 10^(-2) mole% of SrCl_(2) then the number of cation vacancies per mole
Answer» `10.046 XX 10^18` `12.046 xx 10^19` `12.046 xx 10^21` `6.023 xx 10^21` ANSWER :B

Discussion

15.	NaCl is a AB type of solid . Its crystalline structure is known as rock salt structure in which r_"Na"^+ and r_"Cl"^- are 95 and 181 pm respectively , where Cl^- is present at the lattice point of face centered cubic unit cell Na^+ ions are located in void and those compounds which have same crystalline structure also have same coordination system in which Na^+ and Cl^- ions are surrounded by certain number of opposite ions respectively. Under high pressure coordination number changes to 8 :8 type from 6 :6 type. LiCl adopts rock salt crystalline structure in which edge length is 5.40 Å. What would be the radii of Li^+ ?
Answer» 0.89 Å 2.7 Å 1.78 Å 0.98 Å Answer :A

Discussion

16.	NaCl is an example of
Answer» IONIC solid Covalent solid Metallic solid Molecular solid Answer :1

Discussion

17.	NaCl is a AB type of solid . Its crystalline structure is known as rock salt structure in which r_"Na"^+ and r_"Cl"^- are 95 and 181 pm respectively , where Cl^- is present at the lattice point of face centered cubic unit cell Na^+ ions are located in void and those compounds which have same crystalline structure also have same coordination system in which Na^+ and Cl^- ions are surrounded by certain number of opposite ions respectively. Under high pressure coordination number changes to 8 :8 type from 6 :6 type. If the atomic mass of Li and Cl are 7 and 35.5 amu respectively , then what would be number of LiCl molecule in cubic of LiCl withlength x height x breadth = 1 x 1 x 1=1 cm^3 ?
Answer» NEARLY `2.5xx10^22` Nearly `4xx10^20` Nearly `12xx10^30` Nearly `14xx10^23` ANSWER :A

Discussion

18.	NaCl is a AB type of solid . Its crystalline structure is known as rock salt structure in which r_"Na"^+ and r_"Cl"^- are 95 and 181 pm respectively , where Cl^- is present at the lattice point of face centered cubic unit cell Na^+ ions are located in void and those compounds which have same crystalline structure also have same coordination system in which Na^+ and Cl^- ions are surrounded by certain number of opposite ions respectively. Under high pressure coordination number changes to 8 :8 type from 6 :6 type. In rock salt type structure of AB solid , what would be the maximum radius of 'X' that can displace A^+ if radius of B^- is 100 pm ?
Answer» 41.4 pm 73.2 Å 41.4 Å 73.2 pm Answer :D

Discussion

19.	NaCl is an example for diamagnetic substance. Write an example for paramagnetic substance.
Answer» ANSWER :CU2+

Discussion

20.	NaCl, CaCl_2, MgSO_4 are known as 1 - 1, 2 - 1 and 2 - 2 elecrolytes respectively.
Answer» ANSWER :1

Discussion

21.	NaCI is added during electrolysis of fused anhydrous MgCI_(2). Why ?
Answer» SOLUTION :NaCI is ADDED as to lower the FUSION temperature of `MgCI_(2)` and to MAKE the mixture as good conductor of electricity.

Discussion

22.	NaBr , used to produce AgBr for use in photography can be self prepared as follows: Fe+Br_(2) to FeBr_(2) ""…(i) FeBr_(2) + Br_(2) to Fe_(3) Br_(8)""…(ii) (not balanced) Fe_(3)Br_(8) + Na_(2)CO_(3) to NaBr+CO_(2) + Fe_(3)O_(4)""...(iii)"" (not balanced) (At mass: Fe=56, Br=80) If yield of (iii) reaction is 90% then mole of CO_(2) formed when 2.06xx10^(3) gm NaBr is formed
Answer» 20 10 9 440 Answer :B

Discussion

23.	NaBr , used to produce AgBr for use in photography can be self prepared as follows: Fe+Br_(2) to FeBr_(2) ""…(i) FeBr_(2) + Br_(2) to Fe_(3) Br_(8)""…(ii) (not balanced) Fe_(3)Br_(8) + Na_(2)CO_(3) to NaBr+CO_(2) + Fe_(3)O_(4)""...(iii)"" (not balanced) (At mass: Fe=56, Br=80) If the yield of (ii) is 60% & reaction is 70% then mass of iron required to produce 2.06xx10^(3) kg NaBr
Answer» `10^(5)` KG `10^(5)` gm `10^(3)` kg None Answer :C

Discussion

24.	NaBr , used to produce AgBr for use in photography can be self prepared as follows: Fe+Br_(2) to FeBr_(2) ""…(i) FeBr_(2) + Br_(2) to Fe_(3) Br_(8)""…(ii) (not balanced) Fe_(3)Br_(8) + Na_(2)CO_(3) to NaBr+CO_(2) + Fe_(3)O_(4)""...(iii)"" (not balanced) (At mass: Fe=56, Br=80) Mass of iron required to produce 2.06xx10^(3) kg NaBr
Answer» 420 gm 420 kg `4.2 xx 10^(5)` kg `4.2 xx 10^(8)` gm Answer :B

Discussion

25.	NaBH_(4)+l_(2)toXuarr+Yuarr+2Nal X+C_(2)H_(5)OHtoY uarr+D X+HCl to Y uarr +E D gives folowwing colour with flame.
Answer» Red Green Blue No colour Solution :`X:B_(2)H_(6) , Y:H_(2)` `NaBH_(4)+l_(2)to B_(2)H_(6) UARR +H_(2) uarr+2Nal` `B_(2)H_(6)+C_(2)H_(5)OH to H_(2) uarr+ B(OC_(2)H_(5))_(3)` `B_(2)H_(6)+HCl to H_(2) uarr +B_(2)H_(5)Cl`

Discussion

26.	NaBH_4 is used in organic chemistry to covert :
Answer» `gtC=O to gtCH_2` `gtC=O to gtCHOH` `gtC=O` to`-NHOH` ANSWER :B

Discussion

27.	Na[Ah(CN)_(2)] is _______.
Answer» SODIUM aurocyanide Sodium META aluminate Aluminosilicate Sodium dicyano argentate Answer :D

Discussion

28.	Na_(2)SO_(3), NaCl, Na_(2)C_(2)O_(4),Na_(2)CrO_(4),NaNO_(2),CH_(3)CO_(2)Na are separately treated with AgNO_(3) solution. In how many many cases is/are white ppt. obtained?
Answer» Solution :`Na_(2)SO_(3), NaCl, NaNO_(2),CH_(3)CO_(2)NA`

Discussion

29.	Na_(2)SO_(3),NaCl,Na_(2)C_(2)O_(4),Na_(2)HPO_(4),Na_(2)CrO_(4),NaNO_(2),CH_(3)CO_(2)Na are separatelytreated with AgNO_(3) solution in how manycasesis/are whiteppt obtained ?
Answer» Solution :`Na_(2)SO_(3),NaCI,Na_(2)C_(2)O_(4),Na_(2)NO_(3), and CH_3 CO_(2)Na` GIVES white ppt with `AgNO_(3)` of `Ag_(2)SO _(3),AgCI,Ag_(2)C_(2)O_(6),AgNO_(3) and CH_(3)COOAg` respectively but `Na_(2)HPO` and `Na_(2)CrO_(2)` givesyellow ppt of `Ag_(3)PO_(4)` and `Ag_(2)CrO_(4)` respectively

Discussion

30.	Na_(2)SO_(3),Na_(2)S_(2)O_(3),Na_(2)CO_(3),Na_(2)CrO_(4) are separatelytreated with AgNO_(3) solution in how many cases is/arered ppt abtained ?
Answer» Solution :`Na_(2)CrO_(6) `with `AgNO_(2)` givesred ppt of `Ag_(2)CrO_(2)` but other gives WHITE ppt of `Ag_(2)SO_(3)` and `Ag_(2)CO_(3)`

Discussion

31.	Na_2CO_3 and NaHCO_3 may be distinguished by treating their aqueous solution with:
Answer» phenolpthalein Dil. Acid MgO none Answer :D

Discussion

32.	Na_2SeO_4 andNaSO_4show:
Answer» Isomorphism Polymorphism Allotropism Ferromagnetism Answer :A

Discussion

33.	Na_(2)S_(2)O_(3) may react with the compounds given in coloum I. Na_(2)S_(2)O_(3) exhibits the properties of the type given in the coloum II, match the reactants given in coloum I with the type of property/properties given in coloum II. {:(,"Column I(reactant)",,"Coloumn II(type of property shown)"),("a)",Cl_(2),,"p) complexing agent"),("b)",AgBr,,"q) dispropotionation"),("c)","HCl",,"r) only as reductant"),("d)",I_(2),,"s) an antichlor"):}
Answer» ANSWER :A::B::C::D

Discussion

34.	Na_(2)S_(2)O_(3) may react with the compound given in Column-I, Na_(2)S_(2)O_(3)exhibits the properties of the type give in the coloumn-II, matter the reactantsgiven in column-Iwith the type of property, propertiesgiven in Column-II {:("COLUMN-I","COLUMN-II"),((A)SO_(2),(p)"turns acidified "K_(2)Cr_(2)O_(7)" solution green"),((B)CO_(2),(q)"turns blue is Red"),((C )H_(2)S,(r )"turns lime water milky"),((D)H_(2)O_(2),(s) "used for restoring old paintings in the museums"):}
Answer» Solution :A) `K_(2)Cr_(2)O_(7)+3SO_(2)+H_(2)SO_(4) to K_(2)SO_(4)+underset("Green")(Cr_(2)(SO_(4))_(3))+H_(2)O` `Ca(OH)_(2)+SO_(2) to underset("milky")(CaSO_(3))+H_(2)O` In aqueous solution it acts as an acid turns moist litmus red. B) `H_(2)O+CO_(2) to underset("Turns blue to red")underset("Carbonic acid")(H_(2)CO_(3)) Ca(OH)_(2)+CO_(2) to underset("Milky white ppt")(CaCO_(3)darr) ` C) `K_(2)Cr_(2)O_(7)+4H_(2)SO_(4)+3H_(2)S to K_(2)SO_(4)+Cr_(2)(SO_(4))_(3)+7H_(2)O+3S` Aqeuous solution `H_(2)S` acidic because it is a weak dibasic acid. `H_(2)S+H_(2)O to H_(3)O^(+)+S^(2-)` D) The equation used for restoring of old oil painting in the museums. `PbS+4H_(2)O_(2) to PbSO_(4)+4O_(2)`

Discussion

35.	Na_(2)S_(2)O_(3) is formed when
Answer» `Na_2S` is boiled with SULPHUR `Na_2SO_3` is boiled with `Na_(2)S` `Na_2SO_3` is boiled with sulphur `Na_2CO_3` is boiled with conc. `H_2SO_4` ANSWER :C

Discussion

36.	Na_(2)S_(2)O_(3) may react with the compound given in Column-I, Na_(2)S_(2)O_(3)exhibits the properties of the type give in the coloumn-II, matter the reactantsgiven in column-Iwith the type of property, propertiesgiven in Column-II {:("COLUMN-I","COLUMN-II"),("(Reactant)","(Type of property)"),((A)Cl_(2),(p)"Complexing agent"),((B)AgBr,(q)"Disproportionation"),((C )HCl,(r )"Only as reductant"),((D)I_(2),(s) "An antichlor"):}
Answer» Solution :A) `Na_(2)S_(2)O_(3)+Cl_(2)+H_(2)O to Na_(2)SO_(4)+2HCL+S-` Hence it act as antichlor and it is oxidized by `Cl_(2)`. B) `2Na_(2)S_(2)O_(3)+AgBr to Na_(3)[Ag(S_(2)O_(3))_(2)]+NaBr-` Used photography fixing AGENT i.e., COMPLEXING agent. C) `Na_(2)S_(2)O_(3)+2HCl to 2NaCl+SO_(2)+S+H_(2)O-` Disproportional reaction. D) `2Na_(2)S_(2)O_(3)+I_(2) to Na_(2)S_(4)O_(6)+2NaI-` It is oxidized by `I_(2)` quantitatively.

Discussion

37.	Na_(2)S_(2)O_(3) is oxidisedby I_(2) to
Answer» `Na_(2)S` `Na_(2)SO_(4)` `NaHSO_(3)` `Na_(2)S_(4)O_(6)` Solution :`2Na_(2)S_(2)O_(3)+I_(2)RARR Na_(2)S_(5)O_(6)+2NaI`

Discussion

38.	Na_(2)S_(2)O_(3) is oxidized by I_(2) to give
Answer» `Na_(2)S` `NaHSO_(3)` `NaSO_(4)` `Na_(2)S_(4)O_(6)` SOLUTION :`Na_(2)S_(2)O_(3)+I_(2) to underset("SODIUM tetrahionate")(Na_(2)S_(4)O_(6) +NaI)`

Discussion

39.	Na_2S_2O_3 is prepared by
Answer» REACTING `H_2SO_3` with NaOH Reducing `Na_2SO_4` with S in alkaline medium Heating NaOH and S Reducing `Na_2SO_4` with S in acidic medium. Solution :`6NaOH(aq)+4S(s)overset(DELTA)toNa_2S_2O_3(aq)+4Na_2S(aq)+3H_2O(l)`

Discussion

40.	Na_(2)S_(2)O_(3) is oxidised by I_(2) to
Answer» `Na_(2)S` `Na_(2)SO_(4)` `NaHSO_(3)` `Na_(2)S_(4)O_(6)` Solution :`2 Na_(2)S_(2)O_(3) + I_(2) rarr 2 NAI + Na_(2)S_(4)O_(6)`

Discussion

41.	Na_(2)S + Na_(2)[Fe(CN)_(5)NO]to Na_(4)[Fe(CN)_(5)NOS], oxidation number ofFe in rectant (complex) and product (complex) are:
Answer» 2, 1 2, 2 2, 3 3, 3 Answer :D

Discussion

42.	Na_(2)S +Na_(2)[Fe(CN)_(5)NO] to Na_(4) [Fe(CN)_(5)NOS]. Oxidation number of Fe in reactant (complex) and product (complex) are :-
Answer» 2, 1 2, 2 2, 3 3, 3 ANSWER :B

Discussion

43.	Na_2O_(2) is producedc in reaction between H_(2)O_(2) and NaOH. Here the role of H_(2)O_(2) is
Answer» As an OXIDISING agent As an acid As a BASE As a reducing agent SOLUTION :`H_(2)O_(2)` acts as an acid to produce the salt sodium peroxide from the base NaOH `H_(2)O_(2) +2NaOH to Na_(2)O_(2) +2H_(2)O`

Discussion

44.	Na_(2)SO_(3) + HCl rarr Na_(2)SO_(4) + H_(2)O+X X + Na_(2) S overset( Delta )(rarr) S+Y Y + I_(2) rarr NaI +'Z'
Answer» SOLUTION :`H_(2)S_(4)O_(6)`

Discussion

45.	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» ANSWER :5 (All EXCEPT NABR)

Discussion

46.	Na_(2)CO_(3)+SO_(2)overset(Delta)rarr A+B,B+S rarr C andC +2AgNO_(3)rarr 2NaNO_(3)+D. When compound D on exposure to moisture gives black precipitate silver sulphide. What are the substances A and C?
Answer» SOLUTION :`CO_(2),C=Na_(2)S_(2)O_(3)`

Discussion

47.	Na_2CO_3 + Fe_2O_3 rarrA + CO_2, A is:
Answer» `NaFeO_2` `Na_3FeO_3` `Fe_3O_4` `Na_2FeO_2` ANSWER :A

Discussion

48.	Na_(2)CO_(3)+Fe_(2)O_(3) overset(Delta)(to)A+CO_(2) what is A in the reaction?
Answer» `NaFeO_(2)` `Na_(2)FeO_(3)` `Fe_(3)O_(4)` `Na_(2)FeO_(4)` Answer :A

Discussion

49.	Na_(2)CO_(3) cannot be used to identify
Answer» `CO_(3)^(2-)` `SO_(3)^(2-)` `S^(2-)` `SO_(4)^(2-)` SOLUTION :`SO_(3)^(2-),S^(2-)` and `SO_(4)^(2-)` SALTS form comparatively stronger acids (than `H_(2)CO_(3)`) in solution HENCE evolve `CO_(2)` with `Na_(2)CO_(3)` solution and GIVE effervesence. While `CO_(3)^(2-)` does not react with `Na_(2)CO_(3)` solution.

Discussion

50.	Na_(2)CO_(3) cannot be used in place of (NH_(4))_(2)CO_(3) for the precipitate of group V because
Answer» `NA^(o+)`interferes in the detertion of group V Cancentration of `CO_(3)^(2-)` is very low Na will REACTS with acid redicals Mg` will be PRECIPITATE Solution :`Na_(2)CO_(3)` fermishes appreciable `p[CO_(3)^(2-)]` to precipitate `Mg`

Discussion

Explore topic-wise InterviewSolutions in Current Affairs.

{:(NaH_(2)PO_(4) overset( gt 240^(@)C)rarrunderset("Sodium trimetaphosphate")((NaPO_(3))_(3))overset(625^(@)C) rarrunderset("(liquid melt)")(NaPO_(3))),("rapid"darr"cooling"),("D(glass)"):} Compound (D) is known as :

NaHC_(2)O_(4) is 0.1 M when neutralised with NaOH. Hence, it is ...... when oxidised with MnO_(4-)//H^(+) .

NaH crystallizes in the same structure as that of NaCl. The edge length of the cubic unit cell of NaH is 4.88 Å. (a) Calculate the ionic radius of H^(–), provided the ionic radius of Na+ is 0.95 Å. (b) Calculate the density of NaH.

NaCN is sometimes added in the front loatation process as a depressant when ZnS and PbS minerals are expected because

NaClO_(3) is obtained by reacting Cl_(2) and

NaCN is added in froth floation process process with ZnS and PbS minerals because

NaClO solution reacts with H_(2)SO_(3) as, NaClO+H_(2)SO_(3)rarr NaCl + H_(2)SO_(4). A solution of NaClO used in the above reaction contained 15g of NaClO per litre. The normality of the solution would be

NaCl, NaBr, Nal mixture on adding conc. H_(2)SO_(4) gives gases respectively

NaCl ,NaBr , NaI mixtureon adding conc. H_2SO_4 gives gases respectively

NaCl, NaBr and NaI mixture on heating with conc. H_2 SO_4 gives gases respectively.

NaCl + K_(2)Cr_(2)O_(7)+H_(2)SO_(4) rarr NA_(2)SO_(4) + K_(2) SO_(4) +H_(2)O +X The oxidation state chromium in the product X

NaCl is doped with 2xx10^(-3) mole % of SrCl_(2). The concentration of cation vacancies is

NaCZ is doped with 2 xx 10^(-2) mole% of SrCl_(2) then the number of cation vacancies per mole

NaCl is an example of

NaCl is an example for diamagnetic substance. Write an example for paramagnetic substance.

NaCl, CaCl_2, MgSO_4 are known as 1 - 1, 2 - 1 and 2 - 2 elecrolytes respectively.

NaCI is added during electrolysis of fused anhydrous MgCI_(2). Why ?

NaBH_(4)+l_(2)toXuarr+Yuarr+2Nal X+C_(2)H_(5)OHtoY uarr+D X+HCl to Y uarr +E D gives folowwing colour with flame.

NaBH_4 is used in organic chemistry to covert :

Na[Ah(CN)_(2)] is _______.

Na_(2)SO_(3), NaCl, Na_(2)C_(2)O_(4),Na_(2)CrO_(4),NaNO_(2),CH_(3)CO_(2)Na are separately treated with AgNO_(3) solution. In how many many cases is/are white ppt. obtained?

Na_(2)SO_(3),NaCl,Na_(2)C_(2)O_(4),Na_(2)HPO_(4),Na_(2)CrO_(4),NaNO_(2),CH_(3)CO_(2)Na are separatelytreated with AgNO_(3) solution in how manycasesis/are whiteppt obtained ?

Na_(2)SO_(3),Na_(2)S_(2)O_(3),Na_(2)CO_(3),Na_(2)CrO_(4) are separatelytreated with AgNO_(3) solution in how many cases is/arered ppt abtained ?

Na_2CO_3 and NaHCO_3 may be distinguished by treating their aqueous solution with:

Na_2SeO_4 andNaSO_4show:

Na_(2)S_(2)O_(3) is formed when

Na_(2)S_(2)O_(3) is oxidisedby I_(2) to

Na_(2)S_(2)O_(3) is oxidized by I_(2) to give

Na_2S_2O_3 is prepared by

Na_(2)S_(2)O_(3) is oxidised by I_(2) to

Na_(2)S + Na_(2)[Fe(CN)_(5)NO]to Na_(4)[Fe(CN)_(5)NOS], oxidation number ofFe in rectant (complex) and product (complex) are:

Na_(2)S +Na_(2)[Fe(CN)_(5)NO] to Na_(4) [Fe(CN)_(5)NOS]. Oxidation number of Fe in reactant (complex) and product (complex) are :-

Na_2O_(2) is producedc in reaction between H_(2)O_(2) and NaOH. Here the role of H_(2)O_(2) is

Na_(2)SO_(3) + HCl rarr Na_(2)SO_(4) + H_(2)O+X X + Na_(2) S overset( Delta )(rarr) S+Y Y + I_(2) rarr NaI +'Z'

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.

Na_(2)CO_(3)+SO_(2)overset(Delta)rarr A+B,B+S rarr C andC +2AgNO_(3)rarr 2NaNO_(3)+D. When compound D on exposure to moisture gives black precipitate silver sulphide. What are the substances A and C?

Na_2CO_3 + Fe_2O_3 rarrA + CO_2, A is:

Na_(2)CO_(3)+Fe_(2)O_(3) overset(Delta)(to)A+CO_(2) what is A in the reaction?

Na_(2)CO_(3) cannot be used to identify

Na_(2)CO_(3) cannot be used in place of (NH_(4))_(2)CO_(3) for the precipitate of group V because