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.

In which of the following conversions all the three oxygen atoms of O_(3) molecules are utilised for oxidation: I. Ferrous oxide to ferric oxide II. Acidified stannous chloride to stannic chloride III. Moist iodine to iodic acid VI. Sulphur dioxide to sulphur trioxide

Answer»

I and II only
II and IV only
I, III and IV only
II, III and IV only

Answer :B
2.

In this reaction {:(CH_(3)CHO+HCN),(""darr),(CH_(3)CH(OH)CNoverset(H^(+)//OH^(-))rarrCH_(3)CH(OH)COOH):} as asymmetric centre is generated. The acid obtained would be

Answer»

`20% D+ 80% L-`isomer
D-isomer
L-isomer
`50% D + 50% L-`isomer

Solution :`CH_(3)CHO + HCN rarr CH_(3)CHOHCN overset("hydrolysis")rarr underset(D+L"isomer of LACTIC acid")(CH_(3)CHOHCOOH)`
3.

In which of the following conditions a chemical reaction can not occur

Answer»

`DeltaH` and `DeltaS` INCREASE and `TDeltaS gt DeltaH`
`DeltaH` and `DeltaS` decrease and `DeltaH gt TDeltaS`
`DeltaH` increase and `DeltaS` DECREASES
`DeltaH` decrease and `DeltaS` increase

Solution :If `DeltaH=+ve` and `DeltaS=-ve` then the REACTION is non-spontaneous i.e. can not occur.
4.

In this reaction C_(6)H_(5)NH_(2)+HCl+NaNO_(2)rarrX. Product X is

Answer»

ANILINE hydrochloride
Nitro aniline
Benzenediazonium chloride
None of these

Solution :`C_(6)H_(5)NH_(2)+HCl+NaNO_(2)rarrC_(6)H_(5)N_(2)Cl`
5.

In which of the following compounds X is bonded to an sp^(2) carbon-

Answer»



`CH_(2)=CHCH_(2)X`

ANSWER :A::D
6.

In this reaction, CH_(3)CHOtoCH_(3)CH(OH)Cnoverset(H*OH)toCH_(3)CH(OH)COOH An asymmetric centre is generated. The acid obtained would be

Answer»

50%D+50% L-isomer
20%D+80% L-isomer
D-isomer
L-isomer

Solution :Lactic ACID obtained in the given reaction is an optically active compound DUE to the presence of CHIRAL C-atom. It exits as d and l-forms WHOSE ratio is 1:1
7.

In which of the following compounds the ring on the left side undergoes electrophilic substitution reaction -

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ANSWER :D
8.

In which of the following complexes the nickel metal is in highest oxidation state:

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`[Fe(H_2O)_3(OH)_3]`
`[Ni(CO)_4]`
`[Fe(H_2O)_6]SO_4`
`[Co(NH)_3]_6CI_3`

Answer :B
9.

In which of the following compounds, the periodicity of the definite formation is not observed ?

Answer»

`I_(2(s))`
NAPHTHALENE 
FULLERENE 
GLASS 

ANSWER :D
10.

In this case we have A rarrB +C Time ""t" "prop Total pressure of A + B + C""P_(2)" " P_(3) Find k.

Answer»

<P>

SOLUTION :`K=(1)/(t)" In "(P_(3))/(2(P_(3)-P_(2)))`
11.

In which complex is the transition metal in zero. oxidation state:

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`[Fe(H_2O)_3(OH)_3]`
`[Ni(CO)_4]`
`[Fe(H_2O)_6]SO_4`
`[Co(NH)_3]_6CI_3`

ANSWER :B
12.

In third row of periodic table the atomic radii from Na and Cl

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Continuosly decreases
Continuosly INCREASES
Remains constant
Increases but not continuously

SOLUTION :Continuously decreases as the effective NUCLEAR CHARGE increases.
13.

In third group, iron gives blood red colouration with ammonium thiocyanate due to the formation of the compound?

Answer»

FERRIC cyanide
Ferric THIOCYANATE
Ferric thiocyanate ion
Ferric thiocyanide

Solution :`Fe^(3+) + 3 S CN^(-) underset("(Blood RED colouration)")(to Fe (SCN)_(3))`
14.

In which of the following compounds the oxidation state of the nickel atom is zero,

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`KNiCI_3`
`NI(PF_3)_4`
`[Ni(NH_3)_6]CI_2`
`Ni(CO)_4`

ANSWER :D
15.

In third group of qualitive analysis, NH_(4)Cl is added before NH_(4)OH so that

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`OH^(-)` concentration DECREASES
only group III radical get precipitated as HYDROXIDE but others with high solubility product do not
`K_(sp)` of group III hydroxide is high
Group III radicals get precipitated as chlorides

Solution :`NH_(4)OH` is a weak electrolyte and DISSOCIATES partially as `NH_(4)OHhArrNH_(4)^(+)+OH^(-).`
On adding `NH_(4)Cl,` the dissociation of `NH_(4)OH` is suppressed such that `[OH^(-)]` is very less and only less soluble hydroxides are precipitated.
Hence choices (a) and (b) are correct while (c) and (d) are incorrect.
16.

In third row of periodic table from Na to Cl

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ELECTRONEGATIVITY increases
Electronegativity DECREASES
Ionisation ENERGY decreases
Atomic volume increases

Solution :Electronegativity increases SINCE the size decreases.
17.

In which of the following compounds, the nucleophilic character of N - atom is maximum-

Answer»




ANSWER :A
18.

In thermodynamics which one of the following is not an intensive property

Answer»

Pressure
Density
VOLUME
Temperature

Solution :Volume is not an INTENSIVE PROPERTY.
19.

In thermite process the metal used as reducing agent is

Answer»

sodium
aluminium
nickel
zinc

Solution :THERMITE process is used for reducing the high ELECTROPOSITIVE metals like MN, Cr etc. The thermite reagent is a combination of `Fe_(2)O_(3) + AL`
20.

In the Zn-Cu cell, when the concentrations of Zn^(2+) and Cu^(2+)are unity, the e.m.f. is

Answer»

1.75 V
0.5 V
0.0 V
1.1 V

ANSWER :D
21.

In the Victor-Meyer's test, the colours given by 1^(@), 2^(@), and 3^(@) alcohols are, respectively

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RED, COLOURLESS , BLUE
Red, blue , colourless
Red, blue,colourless
Red, blue, violet

Answer :B
22.

In the vulcanisation of rubber:

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Sulpher reacts to FORM a NEW compound.
Sulpher cross-linked are introduced
Sulpher forms a very thin PROTECTIVE LAYER over rubber.
All the statements are correct.

Answer :B
23.

In the Wacker process, the oxidation of ethyne to ethanol is catalysed by____________.

Answer»

SOLUTION :`PdCl_(2)`
24.

In the viscope process the solvent for cellulose consists of

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ETHER and alcohol
Copper SULPHATE and ammonia
sodium hydroxideand CARBON disulphide
Acetic acid and acetic ANHYDRIDE

Answer :C
25.

In the Victor Meyer's method for the determination of molecular mass of an organic compound, what is measured ?

Answer»

Volume of DISPLACED air
Volume of VAPOURS of substance PRODUCED
Volume of water vapours produced
NONE of these

Answer :A
26.

In the valence bond theory, hybridisation of orbitals is an integral part of bond formation.Hybridisation consists of mixing or linear combination of the "pure" atomic orbitals in such a way as to form new hybrid orbitals such as sp, sp^2, sp^3, sp^3d , sp^3d^2 etc. Now answer the following questions : Which of the following are isostructural ? {:(NO_3^(-),CO_3^(2-),CIO_3^(-),SO_3,XeO_3),((I),(II),(III),(IV),"(V)"):}

Answer»

(I) and (IV)
(II) and (V)
(III) and (IV)
(IV) and (V)

SOLUTION :
27.

In the valence bond theory, hybridisation of orbitals is an integral part of bond formation.Hybridisation consists of mixing or linear combination of the "pure" atomic orbitals in such a way as to form new hybrid orbitals such as sp, sp^2, sp^3, sp^3d , sp^3d^2 etc. Now answer the following questions : Which of the following atomic orbitals does not participitate in trigonal bipyramidal hybridisation i.e. sp^3d hybridisation ?

Answer»

s
`d_(x^2-y^2)`
`p_x`
`p_y`

Solution :`{:("HYBRIDISATION","Atomic orbitals","Bond angles","Geometry"),(SP,s+"arbitarary"p^n,180^@,"LINEAR"),(sp^2,s+"arbitarary"p^n,120^@,"Trigonal"),(sp^3,s+"arbitarary"p^n,109.5^@,"Tetrahedral"),(sp^3d,d_((z)^2)+s+p_x+p_y+p_z,90^@","120^@,"Trigonal bipyramidal"),(sp^3d^2,d_((z)^2)+d_(x^2-y^2)+s+p_x+p_y+p_z,90^@,"Octahedral") :}`
28.

InthevanArkelprocess .........is usedto purify.............or........... .

Answer»


ANSWER :IODINE, ZR or TI
29.

In the use of Cl_2 as bleaching agent, the substance that is mainly responsible for the bleaching is

Answer»

`HClO_(2)`
`HClO_(3)`
`HClO_(4)`
`HOCl`

ANSWER :D
30.

In the unsaturatedhydrocarbon compound have

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carbon-carbon DOUBLE bond
carbon-carbon TRIPEL bond
carbon-carbon double and TRIPLE bond
carbon -OXYGEN double bond

Answer :C
31.

In the upper layer of the atmosphere, ozone is formed by the:

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Action of UV RAYS on oxygen
Combination of oxygen molecules
Action of electric DISCHARGE of oxygen molecules
Effect of HIGH pressures on oxygen

Answer :A
32.

In the upper layers of atmosphere, ozone is formed.

Answer»

action of ultraviolet rays on oxygen
action of electric DISCHARGE on oxygen MOLECULES
COMBINATION of oxygen molecules
none

SOLUTION :`O_2 OVERSET"uv"to [O] + [O], O_2 + [O] to O_3`
33.

In the trinitrocellulose, each glucose unit contains how many-OH groups

Answer»

2
3
4
5

Answer :B
34.

In the unit-cell of NaCI lattice there are:

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`3Na^+ION`
`6Na^+ion`
`6Cl- ion`
4NaCI units

Answer :D
35.

In the treatment of waste water discharge, which treatment stage involves biological treatment

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Primary treatment
Secondary treatment
TERTIARY treatment
Reverse osmosis stage

Solution :During waste water treatment
Primary treatment INVOLVES physical process of removing the suspended matters.
Secondary treatment involves BIOLOGICAL treatment
Tertiary treatment involves the removal of phosphate, nitrate and sulphate
36.

In the transition series,starting from lanthanum (._(57)La), the next elements hafnium (._(72)Hf), has an atomicnumberof 72. Why do weobserve this jump in atomic number ?

Answer»

Solution :This is because after `._(57) LA`, filling of 4 f-orbitalstarts which is complete at atomic NUMBER 71.These 14 elements , THEREFORE, BELONG to f-block and placedseparately at the bottom of the periodic table.
37.

In the transition series, with an increase in atomic number, the atomic radius does not change very much. Why is it so ?

Answer»

SOLUTION :This is because electrons are ADDED to inner d-orbitals and EFFECTIVE NUCLEAR charge does not change APPRECIABLY.
38.

In the transition series, with an increase in atomic number, the atomic radius does not change very much. Why is it so?

Answer»

SOLUTION :In case of transition elements, electrons are added into INNER (n - 1) d-orbitals and due to the opposing screening EFFECT of these electrons, EFFECTIVE nuclear charge does not change appreciably.
39.

In the transformation of ""_(92)^(238)U to ""_(92)^(234)U, if one emission is an alpha-particle, what should be the other emission ?

Answer»

Two `beta^(-)` and one `beta^(+)`
One `beta^(-)` and one `gamma`
One `beta^(+)` and one `beta^(-)`
Two `beta^(-)`

SOLUTION :`""_(92)^(238)UTO""_(92)^(234)U+""_(2)^(4)He+2overset(0)-1^(E)`
i.e., `2beta^(-)`
40.

In the transformation of ._(92)^(235)U " to " ._(92)^(234)U, if one emission is an alpha-particle, what should be the other emission (s)

Answer»

TWO `beta^(-)`
Two `beta^(-) and " ONE " beta^(+)`
One `beta^(-) and " one " gamma`
One `beta^(+) and " one " beta^(-)`

Solution :`._(92)^(238)U underset("emission")overset(1 alpha "Particle")rarr ._(92)^(234)Th underset("emission")overset2 beta ("PARTICLES")rarr ._(92)^(234)U`
41.

In the titration of Cl^(-)ions in solution with AgNO_(3) sodium salt of fluorescein is used as an indicator. The equivalence point is marked with the appearance of reddish pink colour. This is due to

Answer»

adsorption of `Cl^(-)`ions by AgCl precipitate particles
adsorption of `NO^(3^(-))`ions by AgCl precipitate particles
adsorption of `AG^(+)`ions by AgCl particles followed by adsorption of FLUORESCEIN anion.
reaction of fluorescein anion with `Ag^(+)` ions in the solution

Solution :After EQUIVALENCE point, the AgCl particles adsorb `Ag^(+)` ions (present in slight excess) and then fluorescein anion. The precipitate particles turn reddish pink DUE to the COMPLEX formation between Ag and fluorescein anion.
42.

In the titration between oxalic acid and acidified potassium permanganate, the manganous salt formed during the reaction catalyses the reaction. The manganous salt acts as:

Answer»

A promoter
A POSITIVE catalyst
An auto-catalyst
None of the above

Answer :C
43.

What is the action of hydrochloric acid on potassium permanganate ?

Answer»

A promoter
A POSITIVE catalyst
An auto-catalyst
None of the above

Answer :C
44.

In the titratin of Fe^(2+) ions with KMnO_(4) in acidic medium, why dilute H_(2)SO_(4) is used and not dilute HCl ?

Answer»

Solution :`KMnO_(4)` in presence of dilute `H_(2)SO_(4)` acts as oxidizing agent and oxygen produced oxidizes FERROUS salt to FERRIC salt
`2KMnO_(4) + 3H_(2)SO_(4) rarr K_(2)SO_(4) + 2MnSO_(4) + 3H_(2)O +5(O)`
`2FeSO_(4) + H_(2)SO_(4) + (O)rarr Fe_(2)(SO_(4))_(3) + H_(2) O ] xx 5`
`bar ( 2KMnO_(4) + 8 H_(2) SO_(4)+ 10 FeSO_(4) rarr K_(2)SO_(4)2MnSO_(4) + 5Fe_(2)(SO_(4))_(3) + 8 H_(2)O)`
`KMnO_(4)`in presence of dilute HCl also acts as oxidizing agent but oxygen produced is usedup partly for OXIDATION of HCl
`2KMnO_(4) + 4HCl rarr 2KCl+ 2MnCl_(2) + 2H_(2)O + 6 (O)`
`2HCL +(O) rarr H_(2)O+ Cl_(2)`
45.

In the thermite process, the reducing agent is :

Answer»

Nickel
Zinc
Sodium
Aluminium

Answer :D
46.

In the thermite process ______ is used as a reducing agent.

Answer»

Al
CO
C
`CO_(2)`

ANSWER :A
47.

In the thermal refining silicates of which metals float as slag on copper ?

Answer»

Ag, Au & PT 
FE, Bi & ZN 
Si, As & Bi 
Sb, Bi & Pt 

Answer :B
48.

Inthethermiteprocess …………… isusedas areucingagent.

Answer»


ANSWER :ALUMINIUM
49.

In the thermal dissociation fo PCl_(5). the partical pressure in the gaseous equlibrium mixture is 1.0 atmosphere when half of PCl_(5) is found to dissociate. The equlibrium constant of the reaction (K_(p)) in atomosphere is

Answer»

<P>`0.25`
`0.50`
`1.00`
`0.3`

SOLUTION :`PCl_(5)overset(hArr)PCl_(3)+Cl_(2)`
`{:("Initial CONC.",1,0,0),("At EQULIBRIUM",0.5,0.5,0.5):}`
`K_(p)=(Px^(2))/((1-x^(2)))=(1xx0.5xx0.5)/([1-(0.5)^(2)])=(0.5xx0.5)/(0.75)=1/3=0.3`
50.

In the thermal decomposition of N_(2)O" at "764^(@)C, the time required to decompose half the reactant was 263 seconds, when the initial pressure was 290 mm of Hg and 212 seconds at an initial pressure of 360 mm of Hg. What is the order of this reaction ?

Answer»

Solution :`(t_(1))/(t_(2))=((a_(2))/(a_(1)))^(n-1)`
`a_(1)="290 mm of HG "t_(1)="263 SECONDS"`
`a_(2)="360 mm of Hg "t_(2)="212 seconds"`
`(263)/(212)=((360)/(290))^(n-1)`
`1.24=(1.24)^(n-1)`
`n-1=1`
`n=1+1=2`
HENCE, the REACTION is of second order.