94420 + Interview Questions in Chemistry in Class 12

1.	The atomic number of bromine is 35 and its atomic weight is 79. Two isotopes of bromine are present in equal amounts. Which of the following statement represents the correct number of neutrons
Answer» `{:("First ISOTOPE","SECOND isotope"),(34,36):}` `{:("First isotope","Second isotope"),(44,46):}` `{:("First isotope","Second isotope"),(45,47):}` `{:("First isotope","Second isotope"),(79,81):}` Solution :Two isotopes of bromine are `._(35)Br^(79), ._(35)Br^(81)` No. of NEUTRONS in `._(35)Br^(79) = 79 - 35 = 44` No. of neutrons in `._(35)Br^(81) = 81 - 35 = 46`

Discussion

2.	The atomic number of an element which shows the oxidation state of +3 is
Answer» 13 32 33 17 Solution :AL SHOWS +3 OXIDATION STATE.

Discussion

3.	The atomic number of an element is 26. The magnetic moment exhibited by its ion in its +2 oxidation state is
Answer» 5.92 BM 2.84 BM 3.87 BM 4.9 BM ANSWER :D

Discussion

4.	The atomic number if vanadium (V), chromiun (Cr), manganese (Mn) and iron (Fe) are respectively 23, 24 , 25, and 26 Which one of these may be expected pt have the highest second ionization enthalphy ?
Answer» Fe V Cr Mn Answer :A

Discussion

5.	The atomic number and electronic configuration of Plutonium respectively are
Answer» `94, 5F^(6)7S^(2)` `95, 5f^(6)7s^(2)` `94, 5f^(7)7s^(1)` `95, 5f^(7)7s^(1)` Answer :A

Discussion

6.	The atomic masses of Li, He and proton are 7.01823 amu, 4.00387 amu and 1.00715 amu respectively. Calculate the energy evolved in the reaction, 3^(Li^(7)) + 1^(H^(1)) rarr 2 2^(He^(4)) + triangle E Given 1 amu = 931 MeV.
Answer» SOLUTION :Mass of reactants = mass of LI + mass of H =7.01823 + 1.00715 =8.02358 amu mass loss during change=(8.02538 -8.00774) amu =0.01764 amu `therefore` energy evolvedduringreaction =0.0176 x 931 MEV =16.423 MeV

Discussion

7.	The atomic masses of Li, He and proton are 7.01823 amu, 4.00387 amu and 1.00715 amu respectively. Calculate the energy evolved in the reaction, 3^(Li^(7)) + 1^(HA^(1)) rarr 2 2^(He^(4)) + triangle E Given 1 amu = 931 MeV.
Answer» Solution :Mass of reactants = mass of Li + mass of H =7.01823 + 1.00715 =8.02358 amu mass LOSS during change=(8.02538 -8.00774) amu =0.01764 amu `therefore` ENERGY evolvedduringreaction =0.0176 X 931 MeV =16.423 MeV

Discussion

8.	The atomic masses of He and Ne are 4 and 20 respectively. The value of de Broglie wavelength of He gas at -73^(@)C is M times that of the de Broglie wavelength of Ne at 727^(@)C. M is …..
Answer» SOLUTION :EQUATION `15, lamda= (H)/(sqrt(2mE))` As `E prop T, lamda prop (h)/(sqrt(2mT))`

Discussion

9.	The atomic mass of oxygen is 16 , hence the electrochemical equivalent (ECE) of oxygen in kg per coulomb is
Answer» `(8 xx 10^(-3))/(96,500)` `(8)/(96,500)` `(16 xx 10^(-3))/(96,500)` `(16)/(96,500)` Solution :Equivalent mass of O = `(16)/(2) = 8` `Z = (E)/(F')` `Z = (8)/(96,500)` gm/COULOMB = `(8 xx 10^(-3))/(96500)` KG/ coulomb .

Discussion

10.	The atomic mass of an element is 27. if valency is 3, the vapour density of the volatile chloride will be:
Answer» 66.75 6.675 667.5 81 Answer :A

Discussion

11.	The atomic mass of an element is 50 (i) Calculate the mass of one atom, in amu (ii) Calculate the mass of 6.022xx10^(23) atoms, in gm (iii) Calculate the number of atoms in its 10 gm (iv) What mass of the element contains 3.011xx10^(20) atoms
Answer» Solution :(i) 50 AMU `""` (ii) 50 GM (iii) `because` 50 gm of element contains `6.022xx10^(23)` atoms `therefore ` 10 gm of element will contain `(6.022xx10^(23))/(50)xx10=1.2044xx10^(22)` atoms (iv) `because 6.022xx10^(23)` atoms weighs 50 gm `therefore 3.011xx10^(20)` atoms weighs `(50)/(6.022xx10^(23))xx3.011xx10^(20)=0.025` gm

Discussion

12.	The atomic composition of the entire universe is approximately given in the table below: {:("Atom","% of total no. of atoms"),(H,93),(He,7):} Hydrogen atoms constitute what percentage of the universe by mass?
Answer» 0.77 0.23 0.37 0.73 Solution :MASS of 93 'H' atoms=93amu Mass of 7 'He' atoms=28amu % HYDROGEN by mass `=(93)/((93+28))xx100=77%`.

Discussion

13.	The atom larger in size as compared to oxygen is:
Answer» N F Ne All Answer :A

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14.	The atom larger in size as compared to oxygen is
Answer» AR XE NE Kr Answer :C

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15.	The atom having the outer electronic configuration 4s^(2)4p^(2)would be in:
Answer» Group 4 and PERIOD 4 Group 2 and period 4 Group 6 and period 3 Group 8 andperiod 5. Answer :A

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16.	The atmospheric gas which cannot produce greenhouse effect is
Answer» `N_2` `H_2O` `CO_2` `O_3` Solution :The heating of the earth due to TRAPPED radiations is called greenhouse effect. The gases which can trap INFRARED radiation given by the SUN to produce greenhouse effect leading to heating up the environment are called greenhouse gases, e.g., `CO_2, H_2O` (water VAPOUR), and OZONE `(O_3)`

Discussion

17.	The ashes of plant contain alkali metals, 90% of which is:
Answer» Li K Na Rb Answer :B

Discussion

18.	The artifical sweetener containing sulphur that has appearance and taste as that of sugar and is stable at cooking temperature is __________ .
Answer» ASPARTAME Saccharin Sucrolose Alitame SOLUTION :

Discussion

19.	The artificially prepared element from lanthanide series is
Answer» europium thulium PROMETHIUM GADOLINIUM ANSWER :C

Discussion

20.	The artificial sweetner containing chlorine that has the appearance and taste as that of sugar and is stable at cooking temperature is
Answer» ASPARTAME SACCHARIN SUCROLOSE Alitame ANSWER :C

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21.	The artificial sweetner aspartame is the methyl ester of the dipeptide
Answer» GLYCYLALANINE Aspartyl PHENYL alanine Phenyl alanyl ASPARTIC acid Alanyl glycine Answer :B

Discussion

22.	The artificial sweetening agent sucrolose is a _______derivative of sucrose
Answer» ANSWER :TRICHLORO

Discussion

23.	The artificial sweetener that has the highest sweetness value in comparison to cane sugar is :
Answer» Sucralose Aspartane Saccharin ALITAME Solution :Alitame is an ARTIFICIAL sweetner that is 2,000 TIMES as SWEET as sugar.

Discussion

24.	The artificial sweetener containing chlorine that has the appearance and taste as the sugar and is stable at cooking temperature is .........
Answer» aspartame saccharin SUCRALOSE ALITAME SOLUTION :sucralose

Discussion

25.	The artificial sweetener containing chlorine that has the appearance and taste as that of sugar and is stable at cooking temperature is
Answer» Aspartame Saccharin Sucralose Alitame Answer :C

Discussion

26.	The artificial sweetener containing chlorine that has the appearance and taste a that of sugar and is stable at cooking temperature is
Answer» Aspartame Saccharin Sucrolose Alitame ANSWER :C

Discussion

27.	The arsenic in a 1.22g sampleof pesticide was converted to AsO_(4)^(3-) by suitable chemical treatment .it was then titrated using Ag^(+) to form Ag_(3)AsO_(4) as a presipitate .If it took 25 mLof 0.102" M " Ag^(+) to reach to equivalence pointin this titration , what is the percentage of arsenicin the pestcide ? (As = 75)
Answer» Solution :The reaction `3Ag^(+) +AsO_(4)^(3-) to Ag_(3)AsO_(4)^(3-)` is not a REDOXREACTION but a precipitation reaction . The equivalent weightsof `AsO_(4)^(3-) and Ag^(+)`= m.e of `Ag^(+)`= MMOL of `Ag^(+)` ` = 0.102 XX 25 = 2.55` Eq. of `AsO_(4)^(3-) = (2.55)/1000 = 0.00255` Mole of `AsO_(4)^(3-) = (0.00255)/3 = 0.00085` Mole of As =`0.00085 xx 75 = 0.06375 ` G Percentage of arsenic in the pesticide `= (0.06375)/(1.22) xx 100` ` = 5.22 ` %

Discussion

28.	The artificial radioactivity was first discovered by:
Answer» Rutherford Sea Borg Einstein Irene Curie Answer :B

Discussion

29.	The art of electroplating was given by:
Answer» Faraday Edison Graham Brugan Answer :A

Discussion

30.	The art of electroplating was given by
Answer» FARADAY EDISON GRAHAM Brugan SOLUTION :Faraday discovereed ELECTROLYSIS .

Discussion

31.	The Arrhenius equation for two first order equation AtoB and CtoD is given by k_1=10^(12)""e^(-81.28(kJ)//(RT)) k_(2) = 10^(11)""e^(-43.10(KJ) RT At what temperature k_(1) becomes equal to k_(2). The unit of activation energy is "kJ"//"mol" "Use" : In 10 = 2.3 "and"R=8.3 J//K//"mol"
Answer» ANSWER :2000

Discussion

32.	The Arrhenius equation for two first order equation A to B "and" C to D "is given by" k_(1) = 10^(16) e^(-79.9 (Kcal)//RT), k_(2) = 10^(12) e ^(-43.1(kcal)//RT)) Calculate the temperature (Kelvin) at which k_(1) becomes equal to k_(2). Given : In 2= 2.3 [Express your answer by dividing it by 1000.]
Answer» ANSWER :2

Discussion

33.	The Arrhenius equation is
Answer» `K=Ae^((EA)/(RT))` `K=e^((Ea)/(RT))` `K=Ae^(-(Ea)/(RT))` K=Ae^(-(RT)/(E_a))` ANSWER :C

Discussion

34.	The Arrhenius equation expressing the effect of temperature on the rate constant of reaction is:
Answer» `K=(E_a)/(RT)` `k=Ae^(-EA//RT)` `k=log_e[(E_a)/(RT)]` `k=e^(-Ea)//RT` ANSWER :B

Discussion

35.	The Arrhenius equation expressing the effect of temperature on the rate constant of a reaction is
Answer» `K = E^(-E_(a)//RT)` `k= E_(a) //RT` `k = log_(e) (E_a)/(RT)` `k = Ae^(-E_(a)//RT)` Answer :d

Discussion

36.	The Arrhenius equation expressing the effect of temperature on the rate constant of a reaction is given as
Answer» `k=E_a/RT` `k=e^(-E_a/RT)` `k=Ae^(-E_a/RT)` `k=In (E_a)/RT` ANSWER :C

Discussion

37.	The arrangement ABC, ABC ... is referred to as
Answer» OCTAHEDRAL CLOSE PACKING Hexagonal close packing Tetrahedral close packing CUBIC close packing Answer :D

Discussion

38.	The arrangment which converts chemical energy of a redox reaction into electrical energy called_____.
Answer» SOLUTION :GALVANIC CELL or VOLTAIC cell

Discussion

39.	The arrangement of X-ions around A^(+) ion in solid AX is given in the figure (not drawn to scale). If the radius of X^(-) is 250 pm., the radius of A is ........
Answer» 104 PM 125 pm 183 pm 57 pm Solution : `(r_A^+)/(r_(X^-)) = 0.414implies r_(A)^(+) + 0.414 XX 250` = 104 pm.

Discussion

40.	The arrangement of spheres in hexagonal close packing (hcp) is :
Answer» ABC ABC......' AAA BBB. AB'AB AA BC ...... ANSWER :A

Discussion

41.	The arrangement of oxygen atoms around phosphorus atoms in P_4O_10 is:
Answer» Pyramidal Octahedral Square planar Tetrahedral Answer :B

Discussion

42.	The arrangement of oxygen atoms around each phosphorous in P_(4)O_(10)
Answer» PYRAMIDAL OCTAHEDRAL Tetrahedral SQUARE PLANAR ANSWER :2

Discussion

43.	The arrangement of ligands in order of their crystal field splitting energies is called ….. .
Answer» SOLUTION :SPECTROCHEMICAL SERIES

Discussion

44.	The arrangement of following compounds: (I) bromomethane (II). Bromoform (III). Chloromethane (IV). Dibromomethane. In increasing order of boiling points is
Answer» `(IV) lt (III) lt (I)lt(II)` `(I)lt(II)lt(III)lt(IV)` `(III)lt(I)lt(IV)lt(II)` `(II)lt(I)lt(IV)lt(II)` Solution :The MAGNITUDE of the boiling point DEPENDS upon the size of the halogen atom and ALSO the number of halogen atoms present. KEEPING this veiw, it is the correct increasing order BOILINGPOINT.

Discussion

45.	The arrangement of followingcompounds : i. bromomethaneii.bromoform iii. Chloromethaneiv. Dibromomethane In the increasing order of their boiling pointis
Answer» `iltii lt iii lt iv` `iilt iiiltilt iv` `iv lt iii ltilt II` `iii ltiltivlt ii` Solution :The INTER molecular forces of attaction become stronger with the increase in SIZE of the MOLECULES. Hence the order of boiling POINTS will be `CH_3 Cl lt CH_3Br lt CH_3Br_2 lt CH_3Br_3`.

Discussion

46.	The arrangement of decreasing order of stability of 'CH_3', 'C_2H_5', '(CH_3)_2CH' and '(CH_3)_3C free radicals is:
Answer» `oversetcdotCH_3gtoversetcdotC_2H_5 GT (CH_3)_2CHgt(CH_3)_3` `(CH_3)_3oversetcdotCgt (CH_3)_2oversetcdotCHgtoversetcdotC_2H_5gtoversetcdotCoversetcdotH_3` `oversetcdotC_2H_5gt oversetcdotCH_3gt(CH_3)_2oversetcdotCHgt(CH_3)_3oversetcdotC` `(CH_3)_3oversetcdotCgt(CH_3)_2oversetcdotCHgtoversetcdotCH_3gtoversetcdotC_2H_5` ANSWER :B

Discussion

47.	The arrangement of Cl^(-)ions in CsCl structure is-
Answer» h.c.p simple cubic f.c.c B.c.c Answer :B

Discussion

48.	The arrangement of (CH_(3))_(3)C-,(CH_(3))_(2)CH-,CH_(3)CH_(2)- when attached to benzene or unsaturated group in increasing order of inductive effect is
Answer» `(CH_(3))_(3)C- LT(CH_(3))_(2)CH- lt CH_(3)CH_(2)-` `CH_(3)CH_(2)_ lt(CH_(3))_(2)CH- lt(CH_(3))_(3)C-` `(CH_(3))_(2)CH- lt(CH_(3))_(3)C- ltCH_(3)CH_(2)-` `(CH_(3))_(3)C- ltCH_(3)CH_(2)- lt(CH_(3))_(2)CH-` Answer :A

Discussion

49.	The arrangement in which electrical energy supplied brings about a redox reaction is called_____.
Answer» SOLUTION :ELECTROLYTIC CELL

Discussion

50.	The arrangement of atoms that characterises a particular stereoisomer is called:
Answer» GEOMETRY of isomer Configuration structural None of the above Answer :B

Discussion

Explore topic-wise InterviewSolutions in Current Affairs.

The atomic number of bromine is 35 and its atomic weight is 79. Two isotopes of bromine are present in equal amounts. Which of the following statement represents the correct number of neutrons

The atomic number of an element which shows the oxidation state of +3 is

The atomic number of an element is 26. The magnetic moment exhibited by its ion in its +2 oxidation state is

The atomic number if vanadium (V), chromiun (Cr), manganese (Mn) and iron (Fe) are respectively 23, 24 , 25, and 26 Which one of these may be expected pt have the highest second ionization enthalphy ?

The atomic number and electronic configuration of Plutonium respectively are

The atomic masses of Li, He and proton are 7.01823 amu, 4.00387 amu and 1.00715 amu respectively. Calculate the energy evolved in the reaction, 3^(Li^(7)) + 1^(H^(1)) rarr 2 2^(He^(4)) + triangle E Given 1 amu = 931 MeV.

The atomic masses of Li, He and proton are 7.01823 amu, 4.00387 amu and 1.00715 amu respectively. Calculate the energy evolved in the reaction, 3^(Li^(7)) + 1^(HA^(1)) rarr 2 2^(He^(4)) + triangle E Given 1 amu = 931 MeV.

The atomic masses of He and Ne are 4 and 20 respectively. The value of de Broglie wavelength of He gas at -73^(@)C is M times that of the de Broglie wavelength of Ne at 727^(@)C. M is …..

The atomic mass of oxygen is 16 , hence the electrochemical equivalent (ECE) of oxygen in kg per coulomb is

The atomic mass of an element is 27. if valency is 3, the vapour density of the volatile chloride will be:

The atomic mass of an element is 50 (i) Calculate the mass of one atom, in amu (ii) Calculate the mass of 6.022xx10^(23) atoms, in gm (iii) Calculate the number of atoms in its 10 gm (iv) What mass of the element contains 3.011xx10^(20) atoms

The atomic composition of the entire universe is approximately given in the table below: {:("Atom","% of total no. of atoms"),(H,93),(He,7):} Hydrogen atoms constitute what percentage of the universe by mass?

The atom larger in size as compared to oxygen is:

The atom larger in size as compared to oxygen is

The atom having the outer electronic configuration 4s^(2)4p^(2)would be in:

The atmospheric gas which cannot produce greenhouse effect is

The ashes of plant contain alkali metals, 90% of which is:

The artifical sweetener containing sulphur that has appearance and taste as that of sugar and is stable at cooking temperature is __________ .

The artificially prepared element from lanthanide series is

The artificial sweetner containing chlorine that has the appearance and taste as that of sugar and is stable at cooking temperature is

The artificial sweetner aspartame is the methyl ester of the dipeptide

The artificial sweetening agent sucrolose is a _______derivative of sucrose

The artificial sweetener that has the highest sweetness value in comparison to cane sugar is :

The artificial sweetener containing chlorine that has the appearance and taste as the sugar and is stable at cooking temperature is .........

The artificial sweetener containing chlorine that has the appearance and taste as that of sugar and is stable at cooking temperature is

The artificial sweetener containing chlorine that has the appearance and taste a that of sugar and is stable at cooking temperature is

The artificial radioactivity was first discovered by:

The art of electroplating was given by:

The art of electroplating was given by

The Arrhenius equation for two first order equation AtoB and CtoD is given by k_1=10^(12)""e^(-81.28(kJ)//(RT)) k_(2) = 10^(11)""e^(-43.10(KJ) RT At what temperature k_(1) becomes equal to k_(2). The unit of activation energy is "kJ"//"mol" "Use" : In 10 = 2.3 "and"R=8.3 J//K//"mol"

The Arrhenius equation for two first order equation A to B "and" C to D "is given by" k_(1) = 10^(16) e^(-79.9 (Kcal)//RT), k_(2) = 10^(12) e ^(-43.1(kcal)//RT)) Calculate the temperature (Kelvin) at which k_(1) becomes equal to k_(2). Given : In 2= 2.3 [Express your answer by dividing it by 1000.]

The Arrhenius equation is

The Arrhenius equation expressing the effect of temperature on the rate constant of reaction is:

The Arrhenius equation expressing the effect of temperature on the rate constant of a reaction is

The Arrhenius equation expressing the effect of temperature on the rate constant of a reaction is given as

The arrangement ABC, ABC ... is referred to as

The arrangment which converts chemical energy of a redox reaction into electrical energy called_____.

The arrangement of X-ions around A^(+) ion in solid AX is given in the figure (not drawn to scale). If the radius of X^(-) is 250 pm., the radius of A is ........

The arrangement of spheres in hexagonal close packing (hcp) is :

The arrangement of oxygen atoms around phosphorus atoms in P_4O_10 is:

The arrangement of oxygen atoms around each phosphorous in P_(4)O_(10)

The arrangement of ligands in order of their crystal field splitting energies is called ….. .

The arrangement of following compounds: (I) bromomethane (II). Bromoform (III). Chloromethane (IV). Dibromomethane. In increasing order of boiling points is

The arrangement of followingcompounds : i. bromomethaneii.bromoform iii. Chloromethaneiv. Dibromomethane In the increasing order of their boiling pointis

The arrangement of decreasing order of stability of 'CH_3', 'C_2H_5', '(CH_3)_2CH' and '(CH_3)_3C free radicals is:

The arrangement of Cl^(-)ions in CsCl structure is-

The arrangement of (CH_(3))_(3)C-,(CH_(3))_(2)CH-,CH_(3)CH_(2)- when attached to benzene or unsaturated group in increasing order of inductive effect is

The arrangement in which electrical energy supplied brings about a redox reaction is called_____.

The arrangement of atoms that characterises a particular stereoisomer is called: