94420 + Interview Questions in Chemistry in Class 12

1.	Resistance of 0.2M solution of an electrolyte is 50Omega. The specific conductance of the solution of 0.5M solution of the same electrolyte is 280Omega. The molar conductivity of 0.5M solution of the electrolyte is S m^(2)mol^(-1) is
Answer» `5xx10^(-4)` `5xx10^(-3)` `5xx10^(3)` `5xx10^(2)` SOLUTION :`x=1.4S//m` `R=50Omega` `M=0.2 ` `K=(1)/(R)xx(l)/(A)` `implies(l)/(A)=1.4xx50m^(-1)`. Now, NEW solution has M=0.5, `R=280Omega` `impliesK=(1)/(R)xx(l)/(A)=(1)/(280)xx1.4xx50=(1)/(4)` `implies lamda_(M)=(K)/(1000xxM)=((1)/(4))/(1000xx0.5)=(1)/(2000)=5xx10^(-4)`

Discussion

2.	Resistance of 0.2 M solution of an electrolyte is 50 Omega. The specific conductance of the solution of 0.5 M solution of same electrolyte is 1.4 S m^(-1) and resistance of same solution of the same electrolyte is 280 Omega. The molar conductivity of 0.5 M solutions of the electrolyte is 5 m^(2) mol^(-1) is
Answer» `5 XX 10^(-4)` `5 xx 10^(-3)` `5 xx 10^(3)` `5 xx 10^(2)` ANSWER :A

Discussion

3.	Resistance of 0.2 m solution of an electrolyte is 50 Ohm^(-1). The specific conductance of the solution is 1.3 Sm^(-1). If resistance of 0.4 m solution of the same electrolyte is 260 Ohm^(-1), its molar conductivity is ………… .
Answer» `62.5 Sm^2 mol^(-1)` `6250 Sm^2 mol^(-1)` `62.5 XX 10^(-4) Sm^2 mol^(-1)` `625 xx 10^(-4) Sm^2 mol^(-1)` ANSWER :C

Discussion

4.	Resistance of 0.2 M electrolytic solution is 50Omega. And its specific conductivity is 1.4 S m^(-1). If specific resistance of 0.5 M same electrolytic solution is 280Omega. Then what is the molar conductivity of 0.5 M electrolytic solution in S m^(2) ?
Answer» `5XX10^(3)` `5xx10^(2)` `5xx10^(-4)` `5xx10^(-3)` SOLUTION :`5xx10^(2)`

Discussion

5.	Resistance of 0.05 M electrolytic solution at 298K temperature is 30.0 Omega. The cross sectional area of conductivity cell having Pt electrode is 3.8cm^(2) and distance between two electrode is 1.5 cm, then what is the molar conductivity of electrolytic solution ?
Answer» SOLUTION :Conductivity constant for cell : `G^()=(l)/(A)=(1.5cm)/(3.8cm^(2))=0.3947cm^(-1)` Where, R=resistance of solution=`30.0Omega` c=concentration of solution=0.05 mol `L^(-1)` Conductivity of solution : `kappa=(G^())/(R)=(1.5cm)/(3.8cm^(2))xx(1)/(30Omega)` `=0.013158cm^(-1)Omega^(-1)~~0.0132" S "CM^(-1)` Molar conductivity : `Lamda_(m)=(1000kappa)/(c)=(1000xx0.0132" S "cm^(-1))/(0.05" mol "cm^(-3))` `=264" S cm"^(2)mol^(-1)`

Discussion

6.	Resemblance between Nb and Ta is because they
Answer» belong to same group of perioidc table have the same MINERAL SOURCE have almost same IONIC and covalent RADII are transition metals ANSWER :C

Discussion

7.	Required amount of crystalline oxalic acid (eq. eq.=63) to prepare N/10 250 ml oxalic acid solution is
Answer» 0.158 g 1.575 g 15.75 g 6.3 g Solution :`N=(W_(B)xx1000)/(ExxV)IMPLIES(N)/(10)=(X xx1000)/(63xx250)""thereforex=1.575gm`

Discussion

8.	Representative elements are elements of
Answer» s - BLOCK s-block and p-block d-block or TRANSITION ELEMENTS d-block and f-block ANSWER :B

Discussion

9.	Representative elements belong to
Answer» s and p-block d-block d and f-block f-block ANSWER :A

Discussion

10.	Represent the galvanic cell in which the reaction Zn(s)+Cu^(2+) (aq) to Zn^(2+) (aq)+Cu(s) takes place.
Answer» SOLUTION :MAY be represented as: `ZN(s)//Zn^(2+) (aq)\|\|CU^(2+) (aq) \|Cu(s)`

Discussion

11.	Represent the galvanic cell in which the following reaction takes place : Zn(s)+2Ag^(+)(aq)toZn^(2+)(aq)+2Ag(s) (i) The reaction taking place at each of its electrodes. (ii) The carriers of current within this cell.
Answer» SOLUTION :(i) At ANDOE, `ZntoZn^(2+)+2E` At cathode, `Ag^(+)+etoAg` (ii) `Zn^(2+)andAg^(+)ions`.

Discussion

12.	Represent the galvanic cell based on the cell reaction given below:Cu+2Ag^+to Cu^(2+)+2Ag
Answer» SOLUTION :`Cu\|Cu^(+2)\|\|Ag^+\|Ag`

Discussion

13.	Represent the chemical forula of iron rust.
Answer» ANSWER :

Discussion

14.	Represent the cell in which the following reaction takes place: Mg(s)+2Ag^(+)(0.0001M)toMg^(2+)(0.130M)+2Ag(s) Calculate its E_(cell). Given that E_(Mg^(2+)//Mg)^(@)=-2.37V and E_(Ag^(+)//Ag)^(@)=+0.80V
Answer» Solution :Here, we are given reduction potential as `E_(Mg^(2+),Mg)=-2.37,E_(AG^(+),Ag)=+0.80V` As the emf of the cel must be positive, this can be so only if oxidation takes PLACE at the MAGNESIUM electrode, hence, the electrode reaction will be `MgtoMg^(2+)+2e^(-)` (At anode) `2Ag^(+)+2e^(-)to2Ag` (At cathode) Thus, the cell may be REPRESENTED as `Mg\|Mg^(2+)(0.130M)\|\|Ag^(+)(0.0001M)\|Ag` Standard emf of the cell will be: `E_(cell)^(@)=`Std. Red. Pot. Of R.H.S. electrode-Std. Red. Pot. Of L.H.S. electrode=0.80-(-2.37)=3.17V The overall reaction is: `Mg+2Ag^(+)hArrMg^(2+)+2Ag""(n=2)` Applying nernst eqn., we get `E_(cell)=E_(Cell)^(@)-(0.0591)/(n)"log"([Mg^(2+)])/([Ag^(+)]^(2))` `E_(cell)=E_(cell)^(@)-(0.0591)/(2)"log"(0.130)/((10^(-4))^(2))=E_(Cell)^(@)-(0.0591)/(2)"log"(0.130)/(10^(-8))` `=3.17-0.02955log(1.30xx10^(7))=3.17-0.02955xx(7.1139)=3.17-0.21=2.96`volt. ALTERNATIVELY, this problem may be solved by first calculating the electrode potentials of the two electrodes separately and then calculating the emf from the electrode potentials.

Discussion

15.	Represent the cell in which the followig reaction takes place, Mg_((s))+2Ag_((0.0001M))^(+)to Mg_((0.130M))^(2+)+2Ag_((s)) Calculate its E_(cell) if E_(cell)^(Theta)=3.17V
Answer» Solution :In this cell `Mg_((s))\|Mg^(2+)` is anode because Mg get oxidized and also `Ag^(+)` is reduced in Ag so on cathode `Ag^(+)\|Ag` will be on RIGHT side. Between these two ELECTRODES salt bridge is DENOTED by two verticle line \|\| and hence the symbolic representation of cell will be `Mg_((s))\|Mg_((0.130M))^(2+)\|\|Ag_((0.0001M))^(+)\|Ag_((s))` Calculation for `E_(cell)` potential is as follows: `E_(cell)=E_(cell)^(Theta)-(RT)/(nF)LN([Mg^(2+)])/([Ag^(+)]^(2))` `therefore E_(cell)=3.17V-(0.0591)/(2)"log"([Mg^(2+)])/([Ag^(+)]^(2))` `=3.17V-(0.0591)/(2)"log"(0.130)/((0.0001)^(2))` `=3.17-0.2955log(1.33xx10^(+7))` `=3.17-0.2955(+7.1139)` `=3.17-0.2099=3.17-0.21=2.96V`

Discussion

16.	Represent the cell in which the following reaction takes place Mg(s)+2Ag^(+)(0.001M) to Mg^(2+)(0.130)+2Ag(s) Calculate E_("cell")" if "E_("cell")^(0)=3.17V.
Answer» Solution :Represent of the cell `Mg//Mg^(2+)(0.130M)\|\|Ag^(+)(0.01M)//Ag` Cell reaction `Mg+2Ag^(+) to Mg^(2+)+2Ag` FORMULA: `E_("cell")=E_("cell")^(0)-(0.059)/(N)LOG""([Mg^(2+)])/([Ag^(+)]^(2)]` Substitution `E_("cell")=3.17-(0.059)/(2)log"" ([0.130])/([0.0001)]^(2))` =2.96V

Discussion

17.	Replacement of -N_2^+Cl^- from benzene diazonium chloride by iodine can be done by using
Answer» HI NaOI `PI_3` KI Answer :D

Discussion

18.	Replacement of N_2^+ X^- can be done by
Answer» `H_3O^+` AQ. NaOH alc. KOH moist `Ag_2O` ANSWER :A

Discussion

19.	Replacement of Cl of chlorobenzene to give phenol requires drastic conditions but chlorine of 2,4-dinitrochlorobenzene is readily replaced because
Answer» `NO_(2)` make ring electron rich at ORTHO and para `NO_(2)` withdrawn `e^(-)` from METAL POSITION `-NO_(2)` donates `e^(-)` at META position `NO_(2)` WITHDRAWS `e^(-)` from ortho/para position Solution :

Discussion

20.	Replacement of diazonium group by halogen atom can be done by the reaction
Answer» Ullmann reaction Fitting reaction Sandmeyer's reaction Friedel CRAFT reaction Answer :C

Discussion

21.	Replacement of diazonium group by chlorine atom can be carried but by use of
Answer» AgCl CuCl `Cu_(2)Cl_(2)` `PCl_(5)` ANSWER :C

Discussion

22.	Replacement of Cl of chlorobenzene to give phenol requires drastic conditions, but Cl of 2,4-dinitrochlorobenzene is readily replaced. This is because
Answer» `-NO_(2)` group makes the RING electron rich at ORTHO and para position `-NO_(2)` group withdraws ELECTRONS from position `-NO_(2)` donates electrons at META position `-NO_(2)` withdraws electrons from ortho and para position. Answer :D

Discussion

23.	Replacement of CI of chloro benzene to give phenol requires drastic condition but CI of 2. 4-6-trinitro chloro benzene is really replaced because
Answer» `NO_2`makes ring electrons RICH at ortho and para positions `NO_2`with DRAWS electrons from meta position `NO_2`donates electrons at meta position `NO_2`WITHDRAWS electrons from ortho, para positions Answer :D

Discussion

24.	Replacement- N_(2)^(+)Cl^(-) frombenzene diazonium chloride byhydrogenatomcanbedone by using
Answer» `H_(3)PO_(2)` `C_(2)H_(5)-OH` `CH_(3) - CHO` both a andb Answer :D

Discussion

25.	Repeateduse of which one of the following fertilizers would increase the activity of the soil ________
Answer» AMMONIUM sulphate Superphosphate of lime Urea Potassium nitrate Answer :A

Discussion

26.	Repeating units teflon is
Answer» `-CF_3-CF_3-` `-CHF_2-CHF_2-` `-CF_2-CF_2-` `-CH_2-CF_2-` ANSWER :C

Discussion

27.	Replacement by -N_(2)^(+)Cl^(-) frombenzenediazonium choridebycan bedone byusing
Answer» HI NaOI `PI_(3)` Kl Answer :D

Discussion

28.	Reonance is due to
Answer» Delocalization of SIGMA ELECTRONS Delocalization of PI electrons MIGRATION of H atoms Migration of protons ANSWER :B

Discussion

29.	Remsay was awarded Noble Prize for the discovery of rare gases in
Answer» `1900` `1902` `1904` `1910` SOLUTION :N//A

Discussion

30.	Removal of unwanted meterial from the ore is called…………….
Answer» SOLUTION :CONCENTRATION

Discussion

31.	Removal of unreacted oxide ore, other metals, non metals associated with isolated crude metal is called ________
Answer» leaching bleaching REFINING liquation Solution :refining

Discussion

32.	Removal of hydrogen atom is easier when it is attached to:
Answer» `1^@` CARBON `2^@` carbon `3^@` carbon Same in all Answer :C

Discussion

33.	Removal of a hydride ion from a methane molecule will give a:
Answer» METHYL radical Carbonium ion Carbanion Methyl group Answer :B

Discussion

34.	..............relieve pain and produces steeps and they are additive.
Answer» SOLUTION :NARCOTIC Analgegics (or) OPIOIDS

Discussion

35.	Relative rate of SN^(1) reaction for t-butyl bromide?
Answer» 37 0.02 `10^(6)` 1 Solution :`CH_(3)^(-)` has a total of 8 electrons in VALENCE shell of central carbon ATOM like NITROGEN atom in ammonia.

Discussion

36.	Relative rate of methyl bromide in SN^(2) reaction is
Answer» 1 0.02 `10^(6)` 37 Solution :Bronotrifluoride is an electron defficent molecule having SIX ELECTRONS around CENTRAL boron ATOM.

Discussion

37.	Relative lowering of vapour pressure of a dilutesolutionof glucose dissolved in 1 kgof wateris 0.002. The molality of the solution is .
Answer» 0.004 0.222 0.111 0.021 Solution :Relativeloweringin vapoure PRESSURE , `(p^(@) - p)/(p^(@)) = x_(2) = 0.002` Molalityof solution MEANS the numberof MOLES of glucose PRESENTIN 100 g of water . `w_(1)= 1000 g, n_(1) = (1000)/(18) = 55.55` `(n_(2))/(n_(2) + 55.55) = 0.002` For dilutesolution , 55.55 + `n_(2) = 55.55` `THEREFORE n_(2) = 0.002 xx 55.55 = 0.1111`

Discussion

38.	Relative lowering of vapour pressure is ____ the mole fraction of the solute.
Answer» EQUAL to equal to half twice THREE times Solution :equal to

Discussion

39.	Relative lowering of vapour pressure of al dilute solution of gluscose dissolved in 1kg of water is 0.002.The molality of the solution is
Answer» `0.004` `0.222` `0.111` `0.021` Solution :(c) : RELATIVE lowering of vapour PRESSURE for dilute solution i.e., `(p^(@) -p_(s))/(p^(@)) ~~ (n_(2))/(n_(1))` Given: `(p^(@)-p_(s))/(p^(@)) = 0.002, n_(1(H_(2)O)) = (1000)/(18)` moles For dilute solution, `n_(2)` is molality `= 0.002 XX = (1000)/(18)` m = 0.111 m

Discussion

40.	Relative lowering of vapour pressure is a colligative property because …………….. .
Answer» It DEPENDS on the CONCENTRATION of a non-electrolyte solute in solution and does not depend on the nature of the solute MOLECULES It depends on NUMBER of particles of electrolyte solute in solution and does not depend on the nature of the solute particles It depends on the concentration of a non-electrolyte solute in solution as on the nature of the solute molecules It depends on the concentration of an electrolyte or non-electrolyte solute in solution as well as on the nature of solute molecules Answer :a,b

Discussion

41.	Relative lowering of vapour pressure is a colligative property because
Answer» It depends on the xoncentration of a non-electrolytesolute in solution and does not depend on the NATURE of the SOLUTE MOLECULES It depends on number of PARTICLES of electrolyte solutein solution and does not depend on the nature of the solute particles. It depends on the concentration of a non-electrolyte solute in solution as well as on the nature of the solute molecules. It depends on the concentration of an electrolyte or non-eletrolyte solute in solution as well as on the nature of solute molecules. Solution :are both CORRECT.

Discussion

42.	Relative lowering of vapour pressure, elevation of boiling point, depression of freezing point and osmotic pressure are important colligative properties of dilute solutions. Relative lowering of vapour pressure of an aqueous dilute solution of glucose is 0.018 What is the mole fraction of glucose in the solution ?
Answer» Solution :Mole fraction of glucose-Relative LOWERING of VAPOUR PRESSURE= 0.018

Discussion

43.	Relative lowering of vapour pressure is a colligative property because ……..
Answer» It depends on the concentration of a non - ELECTROLYTE solute in SOLUTION and does not DEPEND on the nature of the solute molecules. It depends on number of particles of electrolyte solute in solution and does not depend on the nature of the solute particles. It depends on the concentration of a non - electrolyte solute in solution as well as on the nature of the solute molecules. It depends on the concentration of an electrolyte or non - electrolyte solute in solution as well as on the nature of solute molecules. Solution :Explanation : Colligative PROPERTY depends on (A) the concentration of a nonelectrolyte solute in solution, (B) the number of particles of electrolyte solute in solution, & (C ) It does not depend on the nature of solute molecules / particles.

Discussion

44.	Relative decrease in vapour pressure of an aqueous solution containing 2 moles [Cu(NH_(3))_(3)Cl]Cl in 3 moles H_(2)O is 0.50. on reaction with AgNO_(3), this solution will from
Answer» `1 MOL AGCL` `0.25 mol AgCl` `2 mol AgCl` `0.40 mol AgCl` ANSWER :A

Discussion

45.	Relationship between products (Q) and (S) is
Answer» POSITIONAL isomer chain isomer. stereoisomer. FUNCTIONAL isomer. Answer :D

Discussion

46.	What is relation between K_p and K_c?
Answer» ANSWER :`k_P`=`K_c`, `(RT)^DELTAN`

Discussion

47.	Relationship between DeltaG^(@) and K_(P) is…….
Answer» <P>`DeltaG^(@)`=RT In `K_(P)` `DeltaG^(@)` =-RIN `K_(p)` `DeltaG^(@)`=-T In `K_(P)` `DeltaG^(@)`=-RT In `K_(P)` Answer :A

Discussion

48.	Relation between standard cell potential and equilibrium constant is
Answer» `E^(@) = (N RT)/(F)` In K `E^(@)= (RT)/(NF)` In K `E^(@)=(nRF)/(T)` In K `E^(@)=(RF)/(nT)` In K Solution :Nernst EQUATION.

Discussion

49.	Relation between standard e.m.f. of a cell and equilibrium constant is ________.
Answer» SOLUTION :`(E_(CELL)=(2.303RT)/(NF)IogK_c)`

Discussion

50.	Relation between non standard cell potential and concentration of solution at constant temperature is given by. . . . Scientist.
Answer» Faraday Daniell Leclanche Nernst Solution :`E_(cell)=E_(cell)^(THETA)-RT" ln "KAPPA`

Discussion

Explore topic-wise InterviewSolutions in Current Affairs.

Resistance of 0.2M solution of an electrolyte is 50Omega. The specific conductance of the solution of 0.5M solution of the same electrolyte is 280Omega. The molar conductivity of 0.5M solution of the electrolyte is S m^(2)mol^(-1) is

Resistance of 0.2 m solution of an electrolyte is 50 Ohm^(-1). The specific conductance of the solution is 1.3 Sm^(-1). If resistance of 0.4 m solution of the same electrolyte is 260 Ohm^(-1), its molar conductivity is ………… .

Resistance of 0.2 M electrolytic solution is 50Omega. And its specific conductivity is 1.4 S m^(-1). If specific resistance of 0.5 M same electrolytic solution is 280Omega. Then what is the molar conductivity of 0.5 M electrolytic solution in S m^(2) ?

Resistance of 0.05 M electrolytic solution at 298K temperature is 30.0 Omega. The cross sectional area of conductivity cell having Pt electrode is 3.8cm^(2) and distance between two electrode is 1.5 cm, then what is the molar conductivity of electrolytic solution ?

Resemblance between Nb and Ta is because they

Required amount of crystalline oxalic acid (eq. eq.=63) to prepare N/10 250 ml oxalic acid solution is

Representative elements are elements of

Representative elements belong to

Represent the galvanic cell in which the reaction Zn(s)+Cu^(2+) (aq) to Zn^(2+) (aq)+Cu(s) takes place.

Represent the galvanic cell in which the following reaction takes place : Zn(s)+2Ag^(+)(aq)toZn^(2+)(aq)+2Ag(s) (i) The reaction taking place at each of its electrodes. (ii) The carriers of current within this cell.

Represent the galvanic cell based on the cell reaction given below:Cu+2Ag^+to Cu^(2+)+2Ag

Represent the chemical forula of iron rust.

Represent the cell in which the following reaction takes place: Mg(s)+2Ag^(+)(0.0001M)toMg^(2+)(0.130M)+2Ag(s) Calculate its E_(cell). Given that E_(Mg^(2+)//Mg)^(@)=-2.37V and E_(Ag^(+)//Ag)^(@)=+0.80V

Represent the cell in which the followig reaction takes place, Mg_((s))+2Ag_((0.0001M))^(+)to Mg_((0.130M))^(2+)+2Ag_((s)) Calculate its E_(cell) if E_(cell)^(Theta)=3.17V

Represent the cell in which the following reaction takes place Mg(s)+2Ag^(+)(0.001M) to Mg^(2+)(0.130)+2Ag(s) Calculate E_("cell")" if "E_("cell")^(0)=3.17V.

Replacement of -N_2^+Cl^- from benzene diazonium chloride by iodine can be done by using

Replacement of N_2^+ X^- can be done by

Replacement of Cl of chlorobenzene to give phenol requires drastic conditions but chlorine of 2,4-dinitrochlorobenzene is readily replaced because

Replacement of diazonium group by halogen atom can be done by the reaction

Replacement of diazonium group by chlorine atom can be carried but by use of

Replacement of Cl of chlorobenzene to give phenol requires drastic conditions, but Cl of 2,4-dinitrochlorobenzene is readily replaced. This is because

Replacement of CI of chloro benzene to give phenol requires drastic condition but CI of 2. 4-6-trinitro chloro benzene is really replaced because

Replacement- N_(2)^(+)Cl^(-) frombenzene diazonium chloride byhydrogenatomcanbedone by using

Repeateduse of which one of the following fertilizers would increase the activity of the soil ________

Repeating units teflon is

Replacement by -N_(2)^(+)Cl^(-) frombenzenediazonium choridebycan bedone byusing

Reonance is due to

Remsay was awarded Noble Prize for the discovery of rare gases in

Removal of unwanted meterial from the ore is called…………….

Removal of unreacted oxide ore, other metals, non metals associated with isolated crude metal is called ________

Removal of hydrogen atom is easier when it is attached to:

Removal of a hydride ion from a methane molecule will give a:

..............relieve pain and produces steeps and they are additive.

Relative rate of SN^(1) reaction for t-butyl bromide?

Relative rate of methyl bromide in SN^(2) reaction is

Relative lowering of vapour pressure of a dilutesolutionof glucose dissolved in 1 kgof wateris 0.002. The molality of the solution is .

Relative lowering of vapour pressure is ____ the mole fraction of the solute.

Relative lowering of vapour pressure of al dilute solution of gluscose dissolved in 1kg of water is 0.002.The molality of the solution is

Relative lowering of vapour pressure is a colligative property because …………….. .

Relative lowering of vapour pressure is a colligative property because

Relative lowering of vapour pressure is a colligative property because ……..

Relative decrease in vapour pressure of an aqueous solution containing 2 moles [Cu(NH_(3))_(3)Cl]Cl in 3 moles H_(2)O is 0.50. on reaction with AgNO_(3), this solution will from

Relationship between products (Q) and (S) is

What is relation between K_p and K_c?

Relationship between DeltaG^(@) and K_(P) is…….

Relation between standard cell potential and equilibrium constant is

Relation between standard e.m.f. of a cell and equilibrium constant is ________.

Relation between non standard cell potential and concentration of solution at constant temperature is given by. . . . Scientist.