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.

Among the following compounds how many can exhibit tautomerism?

Answer»


SOLUTION :
an EXHIBIT TAUTOMERISM
Discussion
2.

Among the following compounds having highest enol content.

Answer»

`CH_(3)COOCH_(3)`
`CH_(3)COCH_(3)`
`CH_(3)-UNDERSET(O)underset(||)C-CH_(2)-CHO`
`CH_(3)-underset(O)underset(||)C-CH_(2)-underset(O)underset(||)C-OCH_(3)`

ANSWER :C
Discussion
3.

Among the following compound which is/are optically active?

Answer»

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


`H_(3)C-CH_(2)-underset(CH_(3))underset(|)(CH)-NH_(2)`

Solution :A,B,D has no PLANE of symmetry
Discussion
4.

Among the following compoundthat is readily soluble in water is

Answer»

`BeSO_(4)`
`CaSO_(4)`
`SrSO_(4)`
`BaSO_(4)`

SOLUTION :Due to small size of `Be^(2+)` ions , the hydration enthalpy of `BeSO_(4)` is much higher than its lattice enthalpy . HENCE , `BeSO_(4)` ios readily soluble in `H_(2)O`.
Discussion
5.

Among the following cases, in which case mean free path increases

Answer»

With INCREASING altitude 
with increasing TEMPERATURE 
When `O_2` is replaced by `CO_2` molecules 
When density of GAS increased 

Solution :`LAMBDA UARR` with `T and lambda ` with `P darr`. i.e. increased in altitude `lambda darr as sigma uarr.`
Discussion
6.

Among the following carbocation which is more stable

Answer»

`(C_(6)H_(5))`


`CH_(2) = CH`

ANSWER :A
Discussion
7.

Among the following anions, the order of basic strength is "A)" CH_(3)^(-)"B)"NH_(2)"C)"OH-"D)"F-

Answer»

`A gt B gt C gt D`
`B gt A gt C gt D`
`C gt B gt A gt D`
`C gt A gt B gt D`

Solution :Acidic STRENGTH`pm (1)/("BASIC strength of CONJUGATE base ")`
Discussion
8.

Among the following, boiling point is maximum for

Answer»

ISOBUTANE
n-butane
propane
ethane

Answer :B
Discussion
9.

Among the following amphoteric oxide is

Answer»

`BeO`
`Al_(2)O_(3)`
`ZNO`
All the above

Answer :D
Discussion
10.

Among the following, amphoteric element is

Answer»

`C`
`S`
`GE`
`PB`

ANSWER :C
Discussion
11.

Among the following acids which has the lowest pK_(a) value ?

Answer»

`CH_(3)COOH`
`HCOOH`
`(CH_(3))_(2)CH - COOH`
`CH_(3)CH_(2)COOH`

SOLUTION :`HCOOH` is stronest acid and HENCE has HIGHEST `K_(a)` value and lowest `pK_(a)` value
Discussion
12.

Among the following (a)P^(H)of water decreases withincrease in temperature (b)P^(H)of water decrease by the addition of base ©P^(H)of water increases by the addition of acid (d)At anytemperature P^(H)of water is equal toP^(K_w)//2

Answer»

All are correct
B,C,d are correct
a and d are correct
a, b and c are correct

Solution :As ` T uparrow K_W uparrow THEREFORE PK_W uparrow therefore pH uparrow `
on adding BASE pH ` gt ` 7 , on adding acid `pH LT 7 `
Discussion
13.

Among the following (a)On dilution the P^(H)of an acid increases (b)A solution with P^(H)= 5 is 100 times more basic than a solution withp^(H)=3(3)A solution with P^(H)=8 is 1000 times more acidic than a solution with P^(H)=11 (4)The P^(H)of 10 ^(-9)M KOH is slightly greater than

Answer»

All are correct
1, 4 are only correct
1,2,3 are only correct
All are WRONG

SOLUTION :on dilution , pH increase for acid
(b)pH `= 5 RARR [H^(+) ] = 10 ^(-5) `
` pH = 11 rArr [H^(+) ] = 10 ^(-3) `
`therefore 100 `times more basic
( c )`pH = 8 rArr [H^(+) ] = 10 ^(-8)`
`pH = 11 rArr [H^(+) ] =10 ^(-11) `
`therefore 100 `times more acidic
(d)KOH is basic ` 10 ^(-9)` M KOH
`rArr pH GT 7`but slightly GREATER
Discussion
14.

x xx 10^(-2) gm of NaOH should be used up to prepare 200ml of a solution with P^(H)= 12. Find the value of x

Answer»

All are correct
1, 4 are only correct
1,2,3 are only correct
All are wrong

Solution :on dilution , pH increase for acid
(b)pH `= 5 rArr [H^(+) ] = 10 ^(-5) `
` pH = 11 rArr [H^(+) ] = 10 ^(-3) `
`THEREFORE 100 `times more basic
( c )`pH = 8 rArr [H^(+) ] = 10 ^(-8)`
`pH = 11 rArr [H^(+) ] =10 ^(-11) `
`therefore 100 `times more acidic
(d)KOH is basic ` 10 ^(-9)` M KOH
`rArr pH gt 7`but SLIGHTLY GREATER
Discussion
15.

Among the first lines of Lyman,Balmer, paschen and Brackett series in hydrogen atomic spectra,which has the highest energy?

Answer»

Lyman
Balmer
Paschen
Bracket

Answer :A
Discussion
16.

Among the.first lines of Lyman, Balmer, Paschen and Brackett series in hydrogen atomic spectra, which has higher energy?

Answer»

LYMAN
BALMER
Paschen
Bracket

Solution :`E= hc BAR(upsilon) = hc .z^2 R(1/(n_2^2) - 1/(n_2^2))`
Discussion
17.

Among the elements of the third period (Na to Ar), pick out the element that is the most reactive non metal.

Answer»

SOLUTION :Group-17 HALOGENS are all non-metallic and also highly reactive as accepting ONE ELECTRON causes them to attain inert gas configuration. In the third PERIOD chlorine (Cl) shall be the mostreactive non-metal
Discussion
18.

Among the elements of the third period (Na to Ar), pick out the element with the largest atomic radius.

Answer»

Solution :Across the period as NUCLEAR CHARGE INCREASES the size of an element decreases. Alkali metals are undoubtedly the LARGEST in their respective PERIODS. In the third period as a result Sodium (Na) shall be the largest in size.
Discussion
19.

Amongthe elements Li , K Ca S and Krwhichonehas thelowestfirstionization enthalpy ? Whichhasthehighest firstionizationenthalpy ?

Answer»


SOLUTION :Amongthe elements LI, K Ca ,S and Krthe elementsK, Caand Krbelongto 4thperiod . Sincein aperiodalkalimetalhas thelowestand inertgas has thehighest`Delta_(i) H_(1)` thereforeK hasthe lowest`IE_(1)`and Krhasthe highest`Delta_(i) H_(1)`
Discussion
20.

Among the elements of the third period (Na to Ar), pick out the element that is the most reactive metal.

Answer»

Solution :With just ONE valence ELECTRON ALKALI metals not only happen to be the most reactive but also the most electropositive in their period. In the third period sodium (Na) SHALL be the most reactive METAL.
Discussion
21.

Among the elements given below________ has the highest value of electronegativity.

Answer»

Lithium
Ne
F
Be

Answer :C
Discussion
22.

Among the elements In, Ti, TI and Ca which element do not form hydride ?

Answer»

In, TL
In, Tl,Ca
In,Ca
In,Ti

Answer :A
Discussion
23.

Amongthe elementsCa, Mg , P and C1 theorderof increasingatomicradiiis

Answer»

`Mglt Calt C1lt P `
`C1 LT P lt Mg lt Ca`
`P lt C1lt Calt Mg`
`Ca lt Mg lt P lt C1`

Solution :Arrange the elements : Ca, Mg, P andC1 indifferentgroupsand periods in increasingorderfo theiratomicnumberswe have,
`{:("GROUP " to,,12,,15,,17),("Period " 2,,Mg,,P,,C1),("Period " 3 ,,Ca,,-,,-):}`
(i) Sinceatomicradiiincreasefrom top tobottomin a groupthereforeatomicradiusof Ca ismorethan thatof Mg i.e.,`Mg lt Ca`
(ii) Sinceatomicradiidecreases alonga periodfromC1decrease in the order: `Mg gt P gt C1` or increase in THEORDER`: C1 lt P lt Mg`
Combiningthese two trends the atomicradii of`Ca, Mg, P ` andC1 increase inthe order :
`C1 lt P lt Mg lt Ca` i.e.,option ( b)is correct.
Discussion
24.

Amongthe elementsfrom atomicnumber1 to 36the number of elementswhich havean unpairedelectronin the s-subshellis

Answer»

4
7
6
9

Solution :Six elements have oneunpairedelectron in thes-subshell . THESEARE`._(1)H = 1s^(1), ._(3)Li= 2s^(1)`
`._(11)Na = 3s^(1), ._(19) K= [Ar] 4S^(1), ._(24) Cr= [Ar] 3d^(5)4s^(1) ` and `._(29) Cu =[Ar]3d^(10)4s^(1)`
Discussion
25.

Amongthe elements B, Mg , A1 and Kthe correctorder ofincreasingmetalliccharacter is

Answer»

`B LT A1lt Mg lt K`
`B lt Mg lt A1 lt K`
`K lt Mg lt A1 lt B`
`Mg lt A1 lt B lt K`

Solution :Electronegativitydecreasesand hencethe METALLIC characterincreaseswithina groupfromtop tobottom (i.e.,A1 ismore metallicthan B ) .Further , electronegativityincreasesand hencethe metalliccharacterdecreasesfrom leftto rightalong aperiod(i.e.,metalliccharacterdecreasesin the order : `K gt Mg gt A1)`. Thusthe overallmetalliccharacterof the fourelementsincreasesin the order: `B lt A1 lt Mg lt K ,` i.e.,OPTION ( a) iscorrect.
Discussion
26.

Among the elements b, Al, C and Si (a)Which has the highest first ionization enthalpy? (b)Which has the most negative electron gain enthalpy? (c)Which has the largest atomic radius? (d) Which has the most metallic character?

Answer»


Answer :`B lt Al lt MG lt K` (a) C , (b)SI, (c) Al , (d) Al
Discussion
27.

Among the elements B, AI, C and Si, (a) which element has the highest first ionisation enthalpy? (b) which element has the most metallic character ? Justify your answer in each case.

Answer»

Solution :The placing of elements are as

On moving from left to right in a period the IONISATION enthalpy increase with DECREASE in atomic size and also it decreases when we go from top to bottom with increase in atomic size. Hence, carbon has the highest ionisation enthalpy.
(b) Metallic CHARACTER decreases from left to right but increases from top to bottom the GROUP. Therefore, ALUMINIUM has the most metallic character.
Discussion
28.

Among the elements A, B, C and D having atomic numbers 7,8,9 and 12 the element having smallest size is _____

Answer»

`A GT B gt C gt D`
`B gt A gt D gt C`
`B gt A gt C gt D`
`D gt C gt B gt A`

ANSWER :B
Discussion
29.

Amongthe elementB ,A1 , C and Si(i) Whichelementhas thehighestfirstionisationenthalpy? (ii)Whichelement has the mostmetalliccharacter? Justifyyouranswer in theeach case .

Answer»

Solution :ARRANGING theelements B, A1 , C and Siintodifferentgroupsand periods in orderof theirincreasingatomicnumberwe have ,
`{:(" Group " to ,,13,,14),("Period" 2,,B,,C),("Group" 3,,A1,,SI):}`
(i) Sinceionizationenthalpyincreasesalonga PERIODAND decreasesdowna groupthereforeC has thehighestfirstionizationenthalpy
(ii) Sincemetalliccharacterincreasesdowna groupanddecreasesalonga periodthereforeA1 isthe mostmetallicelement .
Discussion
30.

Among the elements A, B, C and D having atomic numbers 9, 10, 11 and 12 respectively the correct order of ionisation energies is

Answer»

`A GT B gt C gt D`
`B gt A gt D gt C`
`B gt A gt C gt D`
`D gt C gt B gt A`

ANSWER :B
Discussion
31.

Among the diffrent kinds of water ,__________is vital for life processes.

Answer»

HEAVY WATER
DEUTERIUM water
protonium water
TRITIUM water

Answer :C
Discussion
32.

Among the compounds NaCl, KCI, RbCI and CsCl, the one with greatest ionic character is

Answer»

NaCI
KCI
CsCI
RbCI

Answer :C
Discussion
33.

Among the compounds given, the one that would form a brilliant colored dye to on treatment with NaNO_(2) in dilute HCl followed by addition to an alkaline solution of beta-napthol is:

Answer»




SOLUTION :N//A
Discussion
34.

Among the alkenes which one produces tertiary butyl alcohol on acidhydration ?

Answer»

`CH_3CH_2CH=CH_2`
`CH_3CH=CHCH_3`
`(CH_3)_2C=CH_2`
`CH_3CH=CH_2`

SOLUTION :`(CH_3)_2C=CH_2+H_2O UNDERSET"Mark.addn."OVERSET(H^+)to underset"tert-Butyl ALCOHOL"((CH_3)_3C-OH)`
Discussion
35.

Among the alkaline earth metals, the element forming predominantly covalent compound is.....

Answer»

Barium
Strontium
Calcium
Beryllium

Answer :D
Discussion
36.

Among the alkaline earth metals, which is radioactive in nature?

Answer»

Beryllium
Calcium
Radium
Barium

Answer :C
Discussion
37.

Among the alkaline earth metals BeOis insoluble in water but oxides are soluble. Why ?

Answer»

Solution :BEO is AMPHOTERIC, oxide is covalent due to the small SIZE of `Be^(2+)`ion. So BeO insoluble in water
Discussion
38.

Among the alkaline earth metal carbonates which one is least stable towards heat ?

Answer»

SOLUTION :`BeCO_3`
Discussion
39.

Among the alkali metals, which element has thelowest ionic radius ?

Answer»

SOLUTION :`LI^(+)`
Discussion
40.

Among the alkali metals which one form compounds with more covalent character?

Answer»

Sodium
Potassium
RUBIDIUM
LITHIUM

ANSWER :D
Discussion
41.

Among the alkali metals, the strongest reducing agent in aqueous medium is

Answer»

L i
N a
K
Rb

Solution :DUE to HIGH HYDRATION energyLi acts as strongreducing agent
Discussion
42.

Among the alkali metal halides, which is covalent? Explain with reason.

Answer»

Solution :All alkali METAL HALIDES are IONIC crystals. However lithium halides shows COVALENT CHARACTER, as it is the smallest cation that exerts high polarising power on the halides.
Discussion
43.

Amongthe alkalimetals, casesiumis thenucleusreactivebecasuse_____.

Answer»

Itsincompleteshellis NEARESTTO THENUCLEUS
ithasasingleelectronmetal
It is theheaviestalkalimetal
theoutermostelectronis morelooselyboundthan theoutermostelectron of theotheralkali METALS

ANSWER :D
Discussion
44.

Among tertiary butyl and isopropyl carbon free radicals, why the first one is more stable ?

Answer»

SOLUTION :In TERTIARY butyl CARBON free radical, nine C - H bonds CONTRIBUTE to hyperconjugative structures and in isopropyl carbon free radical , six C- H bonds contribute.
Discussion
45.

Among solids, the highest melting point is exhibited by

Answer»

Covalent solids
IONIC solids
Pseudo solids
Molecularsolids

Solution :Ionic solids have HIGHEST MELTING point DUETO strong electrostatic forces of ATTRACTION.
Discussion
46.

Among s-block metals and transition metals, which are more metallic?

Answer»

s-block METALS
Transition metals
Both are EQUALLY metallic
Cannot be PREDICTED.

ANSWER :A
Discussion
47.

Among PbS, CuS, HgS, MnS, Ag_(2)S,NiS,CoS,Bi_(2)S_(3), and SnS_(2) the total number of BLACK coloured sulphides is:

Answer»


ANSWER :7
Discussion
48.

Among PbS, CuS, HgS, MnS, Ag_(2)S, NiS, CoS, Bi_(2)S_(3) and SnS_(2), total number of black coloured sulphides is :

Answer»

Four
Six
Five
Three

Solution :`PbS, CUS, HGS, Ag_(2)S, NIS` and CoS are BLACK coloured.
Discussion
49.

Among paraffins, it is generally found that with an increase in molecular weight

Answer»

FREEZING POINT decreases
boiling point increases
boiling point decreases
specific GRAVITY decreases

Answer :C
Discussion
50.

Among ortho, meta and para substituted diahalobezenes which has high melting point ? Give reason with example.

Answer»

Solution :The boiling POINTS of isomeric dihalobenzene are nearly the same . The MELTING POINT of para issomer is generally higher than the melting point of ortho and meta isomers. The higher melting point of p-isomer is due to its symmetry which leads to more close PACKING of its moleculars in the crystal lattice and consequently strong intermolecular attractive force which REQUIRES more energy for melting.
p-Dihalobenzene`gt` o-Dichlorobenzene ` gt` m-Dichlorobenzene.
Discussion