94420 + Interview Questions in Chemistry in Class 12

1.	Elements with their electronic configuration are given below: Answer the following questions:
Answer» I III II V Answer :C

Discussion

2.	Elements with electronic configuration ns^1 are known as
Answer» INERT gases Alkali metals Transuranic elements Halogons Answer :B

Discussion

3.	Elements which posses the characteristics of metals as well as non-metals are called ……………… .
Answer» SOLUTION :METALLOIDS

Discussion

4.	Elements used as semiconductor are purified by
Answer» VAN Arkel method Mond process Distillation Zone REFINING ANSWER :D

Discussion

5.	Elements of which of the following sets has the strongest tendency to form anions?
Answer» N, O and F Ga, In and Te Na, MG and Al V, CR and Mn Answer :D

Discussion

6.	Elements O,S,Se and Te are usually known as:
Answer» Metals Rare EARTH metals Coinage metals Chalcogens Answer :D

Discussion

7.	Elements of which of the following group of periodic table do not formhydrides
Answer» GROUP 7,8,9 group 13 GROUPS 15,16,17 group 14 ANSWER :A

Discussion

8.	Elements of which groups are called d-block elements?
Answer» 1 to 2 3 to 12 13 to 18 13 to 17 Answer :B

Discussion

9.	Elements of which block generally show maximum variation in valency?
Answer» p-block elements s-block elements d-block elements d and s-block elements Answer :C

Discussion

10.	Elements of the zero group possess the configuration :
Answer» `ns^2np^1` `ns^2np^5` `ns^2np^6` `ns^2np^6nd^2` ANSWER :C

Discussion

11.	Elements of IA group give flame colour due to :
Answer» LOW IP Low M.P Softness One ELECTRON in OUTERMOST shell Answer :A

Discussion

12.	Elements of group IVB are:
Answer» STRONGLY electropositive Strongly electronegative Weakly electronegative Neither STRONG nor WEAK electronegative Answer :D

Discussion

13.	Elements of group 16 show lower value of first ionization enthalpy compared to group 15, why ?
Answer» SOLUTION :Element of group 15 have STABLE half-filled p-orbitals, hencelarge amount of energy is required to REMOVE ELECTRONS as compared to group 16, which has an incomplete p SUBSHELL.

Discussion

14.	Elements of group 16 generally show lower value of first ionization enthalpy compared to the corresponding elements of group 15. Why ?
Answer» Solution :This is because of the following two reasons : (i) DUE to extra stability of the exactly half-filled electronic CONFIGURATION of p-orbitals of group 15 elements, they require larger amount of ENERGY to remove an electron as compred to those of group 16 elements. (ii) After REMOVAL of an electron, the group 16 elements yield SPECIES which have more stable exactly half-filled electronic comfiguration of p-orbitals while this is not so in case of group 15 elements.

Discussion

15.	Elements of group-16 generally show lower value of first ionisation enthalpy compared to the corresponding periods of group-15. Why ?
Answer» Solution :Due to extra stable half-filled p-orbitals electronic CONFIGURATIONS of Group-15 ELEMENTS, larger AMOUNT of energy is required to REMOVE electrons COMPARED to Group-16 elements.

Discussion

16.	Group - 16 elements have lower ionisation enthalpy values compared to those group - 15 elements in the corresponding periods. Give reason.
Answer» SOLUTION :This is because of the FOLLOWING two reasons : (i) DUE to extra stability of the exactly HALF - filled P - orbitals electronic configuration of group - 15 elements, they require larger amount of energy to remove and electron as compared to group - 16 elements. (ii) After removal of an electron, the group - 16 elements yields SPECIES which have more stable exactly half - filled p - orbitals electronic configuration while this is not so in case of group - 15 elements.

Discussion

17.	Elements of group-15 form compounds in +5 oxidation state. However, bismuth forms only one well characterised compound in +5 oxidation state. The compound is
Answer» `Bi_(2)O_(5)` `BiF_(5)` `BiCl_(5)` `Bi_(2)S_(5)` Solution :`F_2` being the STRONGEST oxidisng agent, OXIDISES Bi to its HIGHEST O.S. of +5 in `BiF_5`.

Discussion

18.	Elements of group 15 showing allotropic forms are:
Answer» <P>N, SB, Bi N, P, As, Sb As, Sb. Bi P, As, Bi Answer :B

Discussion

19.	Elements of group 15are:
Answer» s-block elements p-block elements d-block elements None Answer :B

Discussion

20.	Elements of group-15 form compounds in (+5) oxidation state. However, bismuth forms only one well characterised compound in (+5) oxidation state. The compound is...........
Answer» `Bi_(2)O_(5)` `BiF_(5)` `BiCl_(5)` `Bi_(2)S_(5)` SOLUTION :`BiF_5` is formed DUE to high electronegativity of fluorine and small size.

Discussion

21.	Elements of group -15 form compounds in +5 oxidation state. However, bismuth forms only one well characterised compound in +5 oxidation state. The compound is
Answer» `Bi_(2)O_(5)` `BiF_(5)` `BiCl_(5)` `Bi_(2)S_(5)` SOLUTION :`F_(2)` being the strongest oxidising AGENT, oxidises Bi to its highest O.S. of +5 in `BiF_(5)`.

Discussion

22.	Elements of group - 15 compounds in +5 oxidation state. However, bismuth forms only one well characterised compound in +5 oxidation state. The compound is
Answer» `Bi_(2)O_(5)` `BiF_(5)` `BiCl_(5)` `Bi_(2)S_(5)` Solution :Stability of + 5 oxidation STATE decreases top to bottem and +3 oxidation state increases top to bottom due to INERT pair EFFECT. Meanwhile compound having +5 oxidation state of Bi is `BiF_(5)`. It is due to smaller SIZE and high electronegativity of fluorine.

Discussion

23.	Elements of group - 15 form compounds in +5 oxidation state. However, bismuth forms only one well characterised compound in +5 oxidation state. The compound is
Answer» `Bi_(2)O_(5)` `BiF_(5)` `BiCl_(5)` `Bi_(2)S_(5)` Answer :B

Discussion

24.	Elements of group 15 form compounds in +5 oxidatin state. However, bismuth forms only one well characterisedcompound in +5 oxidation state. The compound is
Answer» `Bi_(2)O_(5)` `BiF_(3)` `BiCl_(5)` `Bi_(2)S_(5)` SOLUTION :The stability of +5 oxidation state decreases down the group due to inert pair effect. The only well CHARACTERISED Bi(V) COMPOUND is `BiF_(5)` as fluorine being most electronegative element is able to unpair NS ELECTRONS.

Discussion

25.	Elements of group 13 mainly form covalent compounds because
Answer» Size of IONS is small Sum of THREE ionisation ENERGIES is very high Electronegativity values are high All of these Answer :D

Discussion

26.	Elements of group 13 mainly form covalent compounds because _________
Answer» small size electro NEGATIVITY VALUES are HIGH ionizatio ENERGY is very high both (a) and ( c ) Answer :D

Discussion

27.	Elements of group 10 is called pseudo-inert group. Comment.
Answer» Solution :Presence of 18 ELECTRONS in the OUTER most SHELL is called pseudo-octet or pseudo-inert configu-ration. PALLADIUM, a member of GROUP 10 has such configuration.

Discussion

28.	Elements of group 13 form oxides of the general formula :
Answer» `M_4O_5` MO `M_2O_3` `M_2O_4` ANSWER :C

Discussion

29.	Elements of group 1 react violently with water and the solution becomes:
Answer» Acidic Basic Neutral Amphoteric Answer :B

Discussion

30.	Elements of d-group are called
Answer» TRANSITION ELEMENTS Transuranic elements Metals Metalloids Answer :A

Discussion

31.	Elements in which 4f orbitals are progressively filled are called as
Answer» TRANSITION elements Lanthanides ACTINIDES INERT gases Answer :B

Discussion

32.	Elements in the groups 13 to .18 in the periodic table constitute the ‘p’ block elements. Name the most important oxo acid of nitrogen
Answer» SOLUTION :NITRIC ACID `(HNO_3)`

Discussion

33.	Elements in the groups 13 to .18 in the' periodic table constitute the ‘p’ block elements. In general, noble gases are least reactive. Why?
Answer» SOLUTION :Noble gases have STABLE, octet configuration (except for He). HELIUM ALSO has a very stable electronic configuration .of `1 s^2`.So noble gases are chemically unreactive.

Discussion

34.	Elements having different nuclear charge but the same mass number are called
Answer» Isotopes Isobars Isomers Isotones Answer :B

Discussion

35.	......elements does not possess allotropes.
Answer» N Bi P As Answer :A

Discussion

36.	Elements belonging group 16 are called …………….. .
Answer» SOLUTION :CHALGOGENS

Discussion

37.	Elements A, B, C, D belong to the same group. The basic character of their oxides will be in which order if the atomic number of A, B, C, D are (Z – x) , (Z + 2x + 2), Z and (Z + x) respectively:
Answer» `A LT B lt C lt D` `A GT B gt C gt D` `B gt D gt C gt A` `B gt C gt D gt A` ANSWER :C

Discussion

38.	{:("Element","Electronegative value"),(W,2.7),(X,2.1),(Y,0.8),(Z,3.4):} Incorrect statement reagarding given information is:
Answer» WZ does not CONDUCT electricity in SOLID and FUSED state YZ CONDUCTS electricity in solid and fused state XZ conducts electricity only in solution state WX conducts electricity only in fused state Answer :D

Discussion

39.	Elementary unimolecular reaction have first order rate laws, elementary bimolecular reaction have second order rate laws. A rate law is often derived from a proposed mechanismby imposiing the steady state approximation by assuming that there in pre equilibrium A proposal mechanism must be constant with the experimental rate law. The decomposition of O_(3) obeys the mechanism given below, Step 1: O_(3)hArrO_(2)+(O)- fast Step 2: O_(3)+(O)toO_(2)+O_(2)- slow H_(2)+Br_(2)to2HBr Mechaism : Br_(2)hArr2Br (fast) H_(2)+brtoHBr+H(slow) H+BrtoHBR (Fast) Order of the reaction is
Answer» 0<BR>0.1 1.5 0.2 Solution :`K_(C)=([Br]^(2))/([Br_(2)])implies[B_(r)]=SQRT(K_(c).[Br_(2)]),r=K_(2).[H_(2)][B_(r)],r=K_(2).[H_(2)](K_(C))^(1/2).[Br_(2)]^(1/2),r=K.[H_(2)]^(1)[Br_(2)]^(1/2)`

Discussion

40.	Elementary unimolecular reaction have first order rate laws, elementary bimolecular reaction have second order rate laws. A rate law is often derived from a proposed mechanismby imposiing the steady state approximation by assuming that there in pre equilibrium A proposal mechanism must be constant with the experimental rate law. The decomposition of O_(3) obeys the mechanism given below, Step 1: O_(3)hArrO_(2)+(O)- fast Step 2: O_(3)+(O)toO_(2)+O_(2)- slow The milk beacteria growth follows which order of reaction
Answer» 0 1 2 3 Solution :BACTERIAL growth FOLLOWS 1st ORDER KINETICS

Discussion

41.	Elementary unimolecular reaction have first order rate laws, elementary bimolecular reaction have second order rate laws. A rate law is often derived from a proposed mechanismby imposiing the steady state approximation by assuming that there in pre equilibrium A proposal mechanism must be constat with the experimental rate law. The decomposition of O_(3) obeys the mechanism given below, Step 1: O_(3)hArrO_(2)+(O)- fast Step 2: O_(3)+(O)toO_(2)+O_(2)- slow Then find the incorrect one
Answer» ORDER of reaction =1 `r=k[O_(3)]^(2)[O_(2)]^(-1)` Order with RESPECT to `O_(3)=2` Order with respect to `O_(2)=1` Solution :`r=K[O_(3)]^(2)[O_(2)]^(-1)`

Discussion

42.	Element X is strongly electropositive and element Y is strongly electronegative. Both are univalent. The comound formed would be
Answer» `X^(-)-Y` `X-Y^(+)` `X^(+)Y^(-)` `X-Y` ANSWER :C

Discussion

43.	Elements with the general electronic configuration (n-1)d^(3)ns^(2) belong to which group in the modern periodic table ?
Answer» Solution :In case ofd-blockelements group numberis equal to the sum ofns- and `(n-1)d` electrons. ELEMENTS WITHTHE electronic configuration `(n-1)d^(3)ns^2` belong to group 5 or VB group

Discussion

44.	Element with the lowest atomicity
Answer» TE S SE O ANSWER :D

Discussion

45.	Element with pseudooctet configuration in its outermost shell
Answer» Copper Palladium God Platinum Answer :B

Discussion

46.	Element with higher catenation capacity is
Answer» S SE TE PO ANSWER :A

Discussion

47.	Element with atomic number 56 belongs to which block?
Answer» <P>s p d F ANSWER :A

Discussion

48.	Element with atomic number belongs to the period.........and the group ........
Answer» `4^(TH),12^(th)` `4^(th),11^(th)` `5^(th),12^(th)` `5^(th),11^(th)` SOLUTION :Electronic configuration : `[KR]4D^(10)5s^(1)`, period `=5^(th)`, group `=10+1=11^(th)`

Discussion

49.	Element with atomic number 56 belongs to which block ?
Answer» s p d f Answer :D

Discussion

50.	Element with atomic number 49 belongs to the period ……..and the group ……….. .
Answer» `4^(TH), 12^(th)` `4^(th), 11^(th)` `5^(th), 12^(th)` `5^(th), 13^(th)` Answer :D

Discussion

Explore topic-wise InterviewSolutions in Current Affairs.

Elements with their electronic configuration are given below: Answer the following questions:

Elements with electronic configuration ns^1 are known as

Elements which posses the characteristics of metals as well as non-metals are called ……………… .

Elements used as semiconductor are purified by

Elements of which of the following sets has the strongest tendency to form anions?

Elements O,S,Se and Te are usually known as:

Elements of which of the following group of periodic table do not formhydrides

Elements of which groups are called d-block elements?

Elements of which block generally show maximum variation in valency?

Elements of the zero group possess the configuration :

Elements of IA group give flame colour due to :

Elements of group IVB are:

Elements of group 16 show lower value of first ionization enthalpy compared to group 15, why ?

Elements of group 16 generally show lower value of first ionization enthalpy compared to the corresponding elements of group 15. Why ?

Elements of group-16 generally show lower value of first ionisation enthalpy compared to the corresponding periods of group-15. Why ?

Group - 16 elements have lower ionisation enthalpy values compared to those group - 15 elements in the corresponding periods. Give reason.

Elements of group-15 form compounds in +5 oxidation state. However, bismuth forms only one well characterised compound in +5 oxidation state. The compound is

Elements of group 15 showing allotropic forms are:

Elements of group 15are:

Elements of group-15 form compounds in (+5) oxidation state. However, bismuth forms only one well characterised compound in (+5) oxidation state. The compound is...........

Elements of group -15 form compounds in +5 oxidation state. However, bismuth forms only one well characterised compound in +5 oxidation state. The compound is

Elements of group - 15 compounds in +5 oxidation state. However, bismuth forms only one well characterised compound in +5 oxidation state. The compound is

Elements of group - 15 form compounds in +5 oxidation state. However, bismuth forms only one well characterised compound in +5 oxidation state. The compound is

Elements of group 15 form compounds in +5 oxidatin state. However, bismuth forms only one well characterisedcompound in +5 oxidation state. The compound is

Elements of group 13 mainly form covalent compounds because

Elements of group 13 mainly form covalent compounds because _________

Elements of group 10 is called pseudo-inert group. Comment.

Elements of group 13 form oxides of the general formula :

Elements of group 1 react violently with water and the solution becomes:

Elements of d-group are called

Elements in which 4f orbitals are progressively filled are called as

Elements in the groups 13 to .18 in the periodic table constitute the ‘p’ block elements. Name the most important oxo acid of nitrogen

Elements in the groups 13 to .18 in the' periodic table constitute the ‘p’ block elements. In general, noble gases are least reactive. Why?

Elements having different nuclear charge but the same mass number are called

......elements does not possess allotropes.

Elements belonging group 16 are called …………….. .

Elements A, B, C, D belong to the same group. The basic character of their oxides will be in which order if the atomic number of A, B, C, D are (Z – x) , (Z + 2x + 2), Z and (Z + x) respectively:

{:("Element","Electronegative value"),(W,2.7),(X,2.1),(Y,0.8),(Z,3.4):} Incorrect statement reagarding given information is:

Element X is strongly electropositive and element Y is strongly electronegative. Both are univalent. The comound formed would be

Elements with the general electronic configuration (n-1)d^(3)ns^(2) belong to which group in the modern periodic table ?

Element with the lowest atomicity

Element with pseudooctet configuration in its outermost shell

Element with higher catenation capacity is

Element with atomic number 56 belongs to which block?

Element with atomic number belongs to the period.........and the group ........

Element with atomic number 56 belongs to which block ?

Element with atomic number 49 belongs to the period ……..and the group ……….. .