Explore topic-wise InterviewSolutions in Current Affairs.

This section includes 7 InterviewSolutions, each offering curated multiple-choice questions to sharpen your Current Affairs knowledge and support exam preparation. Choose a topic below to get started.

1.

Which of the following group is most basic in the given compounds"

Answer»


ANSWER :2
Discussion
2.

Which branch is not included in the branches of chemistry ?

Answer»

Organic CHEMISRTY
INDUSTRIAL CHEMISTRY
BIOCHEMISTRY
Natural chemistry

Answer :A::C::D
Discussion
3.

Which of the following statements is/are correct ?(1) Two organic compounds with the samse general formula must belong to the same homologous series.(2) Two organic compound with one of the functional groups the same must belong to the same homologous series.(3) Two organic compounds with the molecular mass differing by 14 must belong to the same homologous series.

Answer»

1 only
2 only
1 and 3 only
(b) and (c ) only

Solution :Two ORGANIC COMPOUND with one of the functional groups the same must BELONG to the same homologous series.
Discussion
4.

What weight of magnesia is obtained by complete combustion of two grams of metal?

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SOLUTION :The BALANCED EQUATION for the combustion of magnesium METAL is `2Mg+O_(2) to 2MgO`
2 moles of Mg =2 moles of MGO
1 mole of Mg =1 mole of MgO
24 grams of Mg =40 grams of MgO
The weight of magneisa (MgO) produced by burning 2 grams of metal `=(40)/(24) xx 2=3.333gr`
Discussion
5.

Which of the following alkaline earth metal sulphates is least soluble in water ?

Answer»

`BaSO_(4)`
`MgSO_(4)`
`SrSO_(4)`
`CaSO_(4)`

ANSWER :a
Discussion
6.

When electromagnetic radiation of wavelength 300 nm falls on the surface of sodium, electrons are emitted with a kinetic energy of 1.68 xx 10^(5)J mol^(-1). What is the minimum energy needed to remove an electron from sodium ? What is the maximum wavelength that will cause a photoelectron to be emitted?

Answer»

Solution :Energy of a photon of radiation of wavelength 300 nm will be
`E = hv = h (c)/(lamda) = ((6.626 xx 10^(-34) Js) (3.0 xx 10^(8) ms^(-1)))/((300 xx 10^(-9) m)) = 6.626 xx 10^(-19) J`
`:.` Energy of 1 mole of PHOTONS `= (6.626 xx 10^(-19)J) xx (6.022 xx 10^(23) mol^(-1)) = 3.99 xx 10^(5) J mol^(-1)`
As `E = E_(0) +` K.E. of photoelectrons emitted.
`:.` Minimum energy `(E_(0))` required to remove 1 mole of electrons from sodium `= E -` K.E.
`= (3.99 - 1.68) 10^(5) J mol^(-1) = 2.31 xx 10^(5) J mol^(-1)`
`:.` Minimum energy required to remove one electron `= (2.31 xx 10^(5) J mol^(-1))/(6.022 xx 10^(23) mol^(-1)) = 3.84 xx 10^(-19) J`
The wavelength corresponding to this energy can be calculated using the formula, `E = hv = h (c)/(lamda)`
`:. lamda = (hc)/(E) = ((6.626 xx 10^(-34) Js) (3.0 xx 0^(8) ms^(-1)))/(3.84 xx 10^(-19)J) = 5.17 xx 10^(-7) m = 517 xx 10^(-9) m = 517 nm`
which CORRESPONDS to the green light. As `lamda prop (1)/(E)`, hence when E is minimum, `lamda` is maximum
Discussion
7.

which of the most thermally stable carbonate among MgCO_3,CaCO_3,SrCO3and BaCO3?

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SOLUTION :`BaCO_3`(DUE to GREATER ELECTROPOSITIVITY of BA)
Discussion
8.

Which of the following compounds do not exhibit steroisomerism

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`CH_(3)CH=CHCH_(3)`
`CH_(3)CH=CHCH_(2)CH_(3)`

SOLUTION :
Discussion
9.

The unimolecular nucleophilic substitution is represented by :

Answer»

(II),(III),(Q)
(I),(IV),(S)
(IV),(iv),(Q)
(IV),(iii),(Q)

ANSWER :D
Discussion
10.

Which one of the following is correct about stability of the given ions

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`PB^(2+) gt Pb^(4+)`
`Pb^(4+) gt Pb^(2+)`
`Si^(2+) gt Si^(4+)`
`SN^(4+) gt Sn^(2+)`

ANSWER :A
Discussion
11.

What is the normality of 1 M aq solution of H_(3)PO_(4) ?

Answer»

1 N
4 N
3 N
2 N

Solution :Basicity of `H_(3)PO_(4) = 3 = (3OH^(-))/(H_(3)PO_(4))`
Discussion
12.

Which one of these is not true for benzene ?

Answer»

it FORMS onlye one TYPE of monosubstituted product
there are three CARBON - carbon SINGLE bonds and three carbon-carbon DOUBLE bonds
the heat of hydrogenation of benzene is less than theoretical value
the bond angle between carbon-carbon bond is ` 120^@` .

Solution :
Discussion
13.

Which is more polar -CO_(2) or N_(2) O? Givereason .

Answer»

Solution :`N_(2) O ` is more polar than `CI_(2)` . This is because `CO_(2)`is linear and symmetrical . Its net DIPOLE moment is zero
`(Ooverset(larr)=Coverset(rarr)(=O)) . N_(2) O`is linear but unsymmetrical .It is considered as a reasonance hybrid of the FOLLOWING
two STRUCTRURE :
`:OVERSET(-)overset(. .)N= overset(+)N= overset(. .)O: harr :N-=overset(+)N-overset(-)overset(. .)underset(. .)O:`
It has a net dipole moment of 0.116 D.
Discussion
14.

Using the Periodic Table, predict the formulas of compounds which might be formed by the following pairs of elements, (a) silicon and bromine (b) aluminium and sulphur.

Answer»

Solution :(a) Silicon and Bromine : Silicon is group 14 element with a valence of 4, bromine belongs to the halogen family with a valence of 1. Hence the formula of the COMPOUND formed would be `SiBr_(4)`.
(b) Aluminium and Sulphur : Aluminium belongs to group 13 with a valence of 3, sulphur belongs to group 16 elements with a valence of 2. Hence, the formula of the compound formed would be `Al_(2)S_(3)`.
Discussion
15.

Which of the following gives CH_(3)-OH and CH_(3)-overset(O)overset(||)(C)-CH_(3) on hydrolysis with H_(3)O^(+).

Answer»




`CH_(3)-O-CH_(2)-CH_(2)-CH_(2)-CH_(3)`

SOLUTION :Only C on hydrolysis GIVES `CH_(3)-OH` and `CH_(3)-OVERSET(O)overset(||)(C)-CH_(3)`.
Discussion
16.

Which of the following statement is not true about the hexagonal close packing ?

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The coordination number is 12.
It has 74% PACKING efficiency .
Tetrahedral voids of the second layer are covered by the spheres of the third layer.
In this arrangement spheres of the fourth layer are exactly aligned with those of the FIRST layer.

Solution :In hexagonal close packing , arrangement is ABAB ….. Types and not ABC ABC ……type. Hence, (d) is not TRUE.
Discussion
17.

Which mixture of gases at room temperature does not obey Dalton's law of partial pressure?

Answer»

`NO_(2)andO_(2)`
`SO_(2)andSO_(2)`
CO and `CO_(2)`
`NH_(3)` and HCl

Answer :D
Discussion
18.

Which effect is observed only below a certain temperature?

Answer»

Joule-Thomson effect
Andrew's ISOTHERMAL
VAN DER WAAL equation
Graham's LAW of diffusion

Answer :A
Discussion
19.

The reagent(s) that can selectively precipitate S^(2-) from a mixture of S^(2-) and SO_(4)^(2-) in aqueous solution is (are):

Answer»

`CuCI_(2)`
`BaCI_(2)`
`Pb(OOC CH_(3))_(2)`
`Na_(2)[Fe(CN)_(5)NO]`

Answer :A::C
Discussion
20.

Yield of Ammonia will be more in Haber's process under _____ conditions (L = Low, H = high T = Temp, p = Pressure )

Answer»

LT , LP
LT , HP
HT , HP
HT, LP

Solution : Haber.s PROCESS is EXOTHERMIC
Discussion
21.

Which one is easy, safe and reliable method to make water germ free ?

Answer»

by passing `Cl_2` GAS
by BOILING water
UV RAYS
by proper devices

Solution :by boiling water
Discussion
22.

Which are heterogenous equilibrium ?state the unit of K_c. (i)H_2O_((l)) hArr H_2O_((g)) (ii)Ca(OH)_(2(s)) + aq hArr Ca_((aq))^(2+) + 2OH_((aq))^(-) (iii)CaCO_(3(s)) hArr CaO_((s)) + CO_(2(g)) (iv)CH_3COOC_2H_(5(l)) + H_2O_((l)) hArr CH_3COOH_((l)) + C_2H_5OH_((l)) (v)Fe_((aq))^(3+) + SCN_((aq))^(-) hArr [Fe(SCN)]_((aq))^(2+)

Answer»

Solution :(i)`K_c=[H_2O]="MOL L"^(-1)`
(ii)`K_c=[Ca^(2+)][OH^-]^2 ("mol L"^(-1))^3`
(iii) `K_c=[CO_2] "mol L"^(-1)`
(iv)`K_c=([(CH_3COOH)][(C_2H_5OH)])/([CH_3COOC_2H_5][H_2O])` no UNIT
(V)`K_c=([Fe(SCN)^(2+)])/([Fe^(3+)][SCN^(2+)])`
Thus unit of `K_c` is `("mol" L^(-1))^(-1)` or L `mol^(-1)`
Discussion
23.

Which one of the following electrophile used for nitration of benzene?

Answer»

`BR^(OPLUS)`
`NO_(2)^(oplus)`
`-NH_(2)`
`NO^(oplus)`

ANSWER :B
Discussion
24.

Which of the following ions is the most resonance stabilised?

Answer»

Ethoxide
PHENOXIDE
Butaxide
Isopropoxide

Solution :Phenoxide ION shows maximum RESONATING STRUCTURES.
Discussion
25.

Valence electron in theelementA are 3and that inelementB are6. Mostprobablecompound formedfrom A and Bis

Answer»

`A_(2) B`
`AB_(2)`
`A_(6)B_(3)`
`A_(2)B_(3)`

Solution :`2A: + OVERSET(*****)underset(******)(B) :, (A^(3+))_(2)( :,overset(*****)underset(*****)(B):^(2-))_(3) -= A_(2) B_(3)`
Discussion
26.

What type of difference is observed in hybridization of carbon of benzene during nitration and formaiton of 6 complex ?

Answer»

SOLUTION :Intermediate `SIGMA`-complex is formed in which one carbon POSSESS `sp^(3)` hybridization and rest all carbon possess `sp^(2)` hybridization.
Discussion
27.

Which of the following does not exhibit tautomerism ?

Answer»




Solution :For tautomerism to occur, at least one `alpha`-hydrogen should be presented on a saturated CARBON NEXT to the keto group. Since in OPTION (a), `alpha`-hydrogens are not present on a saturated carbon and hence it does not SHOW tautomerism. While all, other options CONTAIN `alpha`-hydrogens on saturated carbons next to the keto group and hence show tautomerism.
Discussion
28.

Which of the following acts as Lewis base?

Answer»

`SCN^(-)`
`R_2O`
`RNH_2`
All the above

SOLUTION :all have LONEPAIR of ` E^(-) `
Discussion
29.

Which one of the following reagents distinguish ethylene from acetylene?

Answer»

A. Aqueous alkaline `KMnO_4`
B. `Cl_2` dissolved in `"CCL"_4`
C. Ammoniacal `Cu_2Cl_2`
D. CONC. `H_2SO_4`

ANSWER :C
Discussion
30.

What is the oxidation number of carbon in diamond ?

Answer»

`+2`
`+3`
`+4`
0

Solution :Diamond is an alltrope of CARBON, It has carbon atoms bonded with one ANOTHER by covalent bonds.
Discussion
31.

Which fungi is known as insecticide ?

Answer»

TRICHODERMA
Batecorscume
Ossilatrial
None of these

SOLUTION :Trichoderma
Discussion
32.

The values of DeltaH and DeltaS for the reaction, C("graphite") + CO_(2)(g) to 2CO(g) are 170 kJ and 170 J/K respectively. This reaction will be spontaneous at

Answer»

910 K
1110 K
510 K
710 K

Solution :For a spontaneous process , `DeltaG` MUST be negative.
Here, `DeltaG`will be negative when `T DELTAS gt DeltaH`
`DeltaH = 170 kJ = 170000`J
`DeltaS - 170 J K^(-1)"mol"^(-1)`
`TDeltaS gt DeltaH` only when ` T = (DeltaH)/(DeltaS) = (170000)/(170) = 1000K`
i.e greater than 1000 K or 1110 K.
Discussion
33.

What is catenation? Describe briefly the catenation property of carbon.

Answer»

Solution :The tendency of an atom to form a chain of BONDS with the ATOMS of the same element is CALLED CATENATION. The high STRENGTH of C—C bond is responsible for its catenation property.
Discussion
34.

Which one of the following elements does not form triiodide on reacting with iodine?

Answer»

B
Tl
Al
GA

ANSWER :B
Discussion
35.

Which of the following are the values of electron affinities in kJ/mol for the formation of O^(-) and O^(2-) from O ?

Answer»

`-142, -702`
`–141, 702`
`142, 702`
`-142, -142`

ANSWER :B
Discussion
36.

What is the moe fraction of solute in 10% aqueous caustic soda solution?

Answer»


ANSWER :0.047
Discussion
37.

Which of the following processes is most appropriate for the separation of o-nitrophenol and p-nitrophenol from their mixture

Answer»

FRACTIONAL crystallisation
Chromatography
Steam distillation
sublimation

Solution :Steam distillation is USED to separated ORTHO and para nitrophenols from a mixture of them.
Discussion
38.

The valencies of nitrogen and boron in barazole re

Answer»

3,3
4,4
3,4
4,3

Answer :2
Discussion
39.

Which of the following molecules represents the order of hybridisation sp^(2), sp^(2), sp, sp from left to right atoms ?

Answer»

`CH_(3)-CH=CH-CH_(3)`
`HC-=C-C-=CH`
`CH_(2)=CH-CH=CH_(2)`
`CH_(2)=CH-CH-=CH_(2)`

Solution :`UNDERSET(SP^(2))(CH_(2))=underset(sp^(2))(CH)-underset(sp)(C)=underset(sp)(CH)`
Discussion
40.

Which of the following compounds reacts with NaHCO_(3)" giving "CO_(2)

Answer»



`overset(overset(O)(||))(CH_(3)C""COOH)`

Answer :A::B::C::D
Discussion
41.

Write a note on williamson synthesis.

Answer»

Solution :Williamson's synthesis : HELO ALKANES when BOILED with SODIUM alkoxide gives the CORRESPONDING other.
`underset("ethenc")underset("Bromo")(CH_(3)-CH_(2))Br+underset("sodium")underset("ethoxide")(CH_(3)CH_(2)ONa)toCH_(3)-CH_(2)-underset("Diethyl ether")(CH_(2)-CH_(3)+)NaBr`
Discussion
42.

Two substances with the same reduced pressure and the same reduced temperature will have the same reduced volume. This is called

Answer»

Gay-Lussac's LAW
Law of CORRESPONDING states
Law of RECIPROCAL proportions
Continuity of state

Solution :It is the STATEMENT of law of corresponding staes.
Discussion
43.

When 2-bromobutane reacts with alcoholic KOH, the products formed are ………………… .

Answer»

SOLUTION :1-butene & 2-butene
Discussion
44.

The stabillity of +5 oxidation state dereases down the group 15 of the periodic table. Explain this observation giving appropriate reasons.

Answer»

Solution :All the elements of GROUP 15 have five electrons in the valence shell, two in the s-subshell and three in the p- subshell. Therefore, among others, they can show positive oxidation states of +3 (due to pacticipation of only p-electrons) and +5 (due to the participation of both s- and p-electrons of the valence shell). Now N does not have d- or -f -electrons but all other elements have either d-or both d-and f-electrons in the inner shells. Since d-and f-electrons shield the s-electrons of the valence shell more effectively than the p-electrons, therefore on moving down the group tendency of s-electrons to participate in bond FORMATION decreases while that of p electrons increases. As a resulty among hevier elements of group 15, the electron pair in s-orbtial of the valence shell shows reluctance to participate in bond formation. In other words, among heavier elements, only p-electrons participate in bond formation and hence show an oxidation state of +3. This is called inert pair effect. Further, as the NUMBER of d-and f-electrons increases down the group, the inert pair efferct becomes more and more pronounced. In other words, down the group from As to Bi, the stability of +3 oxidation state increases while that of +5 oxidation state decreases.
Discussion
45.

What are unsaturated hydrocarbons

Answer»

SOLUTION :Hydrocarbonshavinglocalised CARBON- carbon multinglebondsare calledcalledunsaturatehydrocarbons . Examplealkenesalkynes.
Discussion
46.

The synthesis of higher alkyne from lower alkyne is achieved by adding a bromo alkane in to amixture of Sodium amide and an alkyne. Which of the following combination(s) of bromoalkane and alkyne, can lead to the formation of 3-Octyne.

Answer»

1-bromo pentane and propyne
1-bromo butane and butyne-2
1-bromo butane and butyne-1
1-bromopropane and pentyne-1

Solution :The above REACTION is possible only with terminal (acidic) alkynes. Hence option "B". is not CORRECT as it is non-terminal alkyne
Discussion
47.

Which is the only isotope that does not contain a neutron?

Answer»

Protium
Dutrium
Tritium
Chlorin-35

Answer :A
Discussion
48.

Which of the following statement/s is/are incorrect about H_(2)O_(2) ?

Answer»

It trus BLUE litmus RED
It NEUTRALISES NAOH (aq)
It LIBERATES `CO_(2)` from `NaHCO_(3)` solution
All statements are correct.

Answer :D
Discussion
49.

What is reversible reaction ? Give examples.

Answer»

Solution :A reaction in which not only the reactants react to form the PRODUCTS under certain condition but also the products react to form reactants under the same condition is CALLED a reversible reaction. It is represented by puting (`hArr` ) double arrow.
e.G. `H_(2(g)) + I_(2(g)) overset(445^@ C)hArr 2HI_((g))`
Discussion
50.

Which of the following equations depict the oxidising nature of H_2O_2?

Answer»

`2MnO_4^(-) + 6H^(+) + 5H_2O_2 to 2Mn^(2+) + 8H_2O + 5O_2`
`2Fe^(3+) + 2H+ H_2O_2 to 2Fe^(2+) + 2H_2O+ O_2`
`2I^(-) + 2H^(+) + H_2O_2 to I_2 + 2H_2O`
`KIO_4 + H_2O_2 to KIO_3 + H_2O + O_2`

SOLUTION :In this reaction reduction of `H_2O_2` is OCCURS e.g. in reaction the OXIDATION no. of OXYGEN atom is become -1 to 2 so its indicate the oxidising nature.
Discussion