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.

What mass of Calcium carbonate is to be decomposed to obtain 4.4 of CO_(2) in the following reaction CaCO_(3)toCaO+CO_(2) (Molecular mass of CaCO_(3)=100)

Answer»


ANSWER :`100xx4.4/4.4=10g` or G
Discussion
2.

What 'X' in the following reaction ? C_(6)H_(5) -C-=C-H overset(Hg^(+2))underset("dil" .H_(2)SO_(4))rarr X

Answer»

`C_(6)H_(5) - COCH_(3)`
`C_(6)H_(5) - CH_(2)CHO`
`C_(6)H_(5) - CHO`
`C_(6)H_(5) - CH_(2)OH`

Answer :A
Discussion
3.

Which of the following alkane can be synthesized by the wurtz reaction in good yield?

Answer»

`(CH_3)_2CHCH_2 CH(CH_3)_2`
`(CH_3)_2CHCH_2CH(CH_3)_2`
`CH_3 CH_2C (CH_3)_2CH_2CH_3`
`(CH_3)_3C CH_2CH_3`

SOLUTION :SYMMETRICAL ALKANES can be prepared in good YIELDS.
Discussion
4.

Water molecule has bent structure whereas carbon dioxide molecule is linear

Answer»

Solution :In `H_(2)O`, OXYGEN atom is `sp^(3)` hybridised with two lone PAIRS. The four `sp^(3) ` hybridised ORBITALS possess a tetrahedral geometry with two comers occupied by hydrogen atoms and other two by the lone pairs.
The bond angle is REDUCED to `104,5^(@)` from `109.5^(@)`because of greater repulsive forces between lp - Ip and the molecule so gain V-shape or bent structure (angular structure).

In `CO_(2)` molecule, carbon atom is sp-hybridised. The two sp hybrid orbitals are ORIENTED in opposite direction forming an angle of `180^(@)`.

So `H_(2)`Omolecule has bent structure and `CO_(2)` molecule is linear.
Discussion
5.

Which plant extract act as insecticides ?

Answer»

Neem
Ak
Dhatura
All of these

Solution :All of these
Discussion
6.

What is order of first second and third ionisation enthalpy? Why?

Answer»

Solution :First ionisation ENTHALPY of element is less than second ionisation enthalpy of element.
Second ionisation enthalpy of element is less than third ionisation enthalpy of element.
Order : `3^(rd) gt 2^(nd) gt 1^(st)` ( ionisation enthalpy)
Because, positive charge INCREASES attraction increases, so more ENERGY is required to lose electron.
Discussion
7.

Which one of the following forms micelles in aqueous solution, above certain concentration.

Answer»

GLUCOSE
Urea
Deodecyltrimethylammonium CHLORIDE
Pyridinium chloride.

SOLUTION :Dodecyl trimethyl ammonium chloride `[C_(12)H_(25)N^(+)(CH_(3))_(3)]Cl^(-)` will form micelles in aqueous solution above certain concentration. Here the cation has a polar ionic head and non-polar tail, required for micelle formation.
Discussion
8.

Write the conjugate acids for the following Bronsted bases : NH_2^(-) , NH_3 and HCO_3^(-) .

Answer»

SOLUTION :`NH_3 , NH_4^(+)` and `H_2CO_3`
Discussion
9.

Which of the following is a secondary haloalkane'?

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BROMOETHANE
2-Chloropropane
2-lodo-2-methylpropane
1-Chloropropane

SOLUTION :2-Chloropropane
Discussion
10.

Which of the following orders orders is true regarding the acidic nature of phenol ?

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PHENOL `GT` o-cresol `LT` nitrophenol
phenol `lt` o-cresol `lt` nitrophenol
phenol `gt` o-cresol `gt` nitrophenol
phenol `lt` o-cresol `gt` nitrophenol

Answer :A
Discussion
11.

Which compound show tautomerism:

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NONE of these

Solution :
Discussion
12.

X is

Answer»




ANSWER :A::B::C::D
Discussion
13.

Which of the following is not an ore of Mg?

Answer»

Gypsum
Magnesite
Dolomite
Carnalite

Answer :A
Discussion
14.

Which one of the two, CIO_(2)6(-) or CIO_(4)^(-) shows disproportionation reaction and why ?

Answer»

Solution :The oxidation state of CI in `CIO_(2)^(-)` is `+3`. So, CHLORINE can get oxidised as well as reduced and can ACT as reductant and oxidant.
The disproportionation reaction of `CIO_(2)^(-)` is `overset(+1)(3CI)O_(2)^(-)to CI^(-)+overset(+5)CIO_(3)^(-)`
In `CIO_(4)^(-),CI` is in its highest oxidation state, So it can only be an oxidant.
Discussion
15.

Which of the following compounds is odd from the remaining

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`NaNO_(3)`
`KNO_(3)`
`LiNO_(3)`
`RbNO_(3)`

Answer :C
Discussion
16.

What is isonisation enthalpy?

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Solution :Energy REQUIRED to lose 1 mole ELECTRON is KNOWN as ionisation enthalpy.
"Energy requird to lose one electron from .mole neutral atom is known as Ionisation enthalpy".
`X_((G)) + Delta_(i)H = X_((g))^(+) + e^(-)`
Where , `Delta_(i) H ` = FIRST Ionisation Enthalpy.
Discussion
17.

Which one of the following has zero dipole moment?

Answer»

1) HF
2) `H_(2)`
3) CO
4) NO

Solution :NO
Discussion
18.

Wurtz reaction involves the comdensation of two molecules of alkyl halides in the presence of sodium and dry ether R-X+2Na+R-Xoverset("dry ether")toR-R+2NaX In this reaction small amount of alkene is also formed as by product. CH_(3)CH_(2)Br+CH_(3)CH_(2)Broverset("Na/dry ether")toCH_(3)-CH_(2)-CH_(2)-CH_(3)+underset("By-product")ubrace(CH_(2)=CH_(2)+CH_(3)-CH_(3)) Tertiary alkyl halides do not give wurtz reaction. Frankland reaction is similar but has certain advantages over wurtz reaction. it is useful in the synthesis of symmetrical alkanes. frankland reaction is shown by primary, Secondary as well as tertiary alkyl halide. Q. Among all isomers of hexane which of the following isomer cannot be obtained in a good yield by wurtz reaction (from symmetrical alkyl halides)? 1. n-hexane 2. iso hexane 3. 2,3-dimethyl butane 4. neo hexane

Answer»

1,4
2,4
1,3
3,4

Answer :B
Discussion
19.

Which of the following reactions is used to bring about the following conversion ?

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Hofmann reaction
CURTIUS reaction
Ritter reaction
Schmidt reaction

Solution :SEE properties of ACIDS
Discussion
20.

Which of the following quantum numbers are not possible ?

Answer»

n = 2,L = 1, m = -1, s = -1/2
n = 3,l = 2, m = -3, s = + 1/2
n = 2,l = 0, m = 0, s = +1/2
n = 3,l = 2, m = -2, s = +1/2

Solution :`l=2 , m_l =-2 ` to` -2 ` but not m = - 3.
Discussion
21.

Write the steps and energy change of formation of ionic bond.

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SOLUTION :To form positive ION : Ionization enthalpy is always endothermic.
To from NEGATIVE ion : ELECTRON gain enthalpy is always exothermic.
To form SOLID : Lattice enthalpy is always more exothermic reaction
Discussion
22.

What is E_(O_3)in the following reaction, 2O_3 rarr 3O_2

Answer»

16
48
32
8

Solution :`2O_3 rarr 3O_2`
2moles of `O_3 = 3xx 4 ` eq of `O_2 (E_(O_2) =32/4)`
1 MOLE of `O_3 = ` 6eq of `O_2`
1 eq. of `O_2 = (48)/6 GM O_3`
1 eq of `O_ 2 = (48)/6 gm O_3`
1 eq of `O_2 =8g ` of `O_3`
Discussion
23.

What will be the pressure of the gaseous mixture when 0.5 L of H_(2) at 0.8 bar and 2.0 L of dioxygen at 0.7 bar are introduced in a 1 L vessel at 27^(@)C ?

Answer»

Solution :Dihydrogen Gas `(H_(2))`
Volume `V_(H_(2))=0.5 L`
PRESSURE `p_(H_(2))=0.8` bar
Dihydrogen Gas `(O_(2))`
Volume `V_(O_(2))=2` Lit
Pressure `p_(O_(2))=0.7` bar
Temperature `= 27^(@)C=300 K` Which is constant
Volume of mixture `= V_("total")=1` Lit.
Calculation of Partial Presure of dil hydrogen gas `pH_(2)` of 1 Lit. Volume :
`p_(1)V_(1)=p_(2)V_(2)`
`therefore ("0.8 bar")(0.5 L) = p_(2)xx1L`
`therefore p_(2)=(("0.8 bar")(0.5 L))/(1L)`
`therefore p_(2)=0.4` bar `= p_(H_(2))`
where, At gas `H_(2)`
`p_(1)=0.8` bar
`V_(1)=0.5 L`
`V_(2)=1L`
`p_(2)=(?)`
Caslculation of Partial Pressure of di Oxygen gas `(PO_(2))` of 1 lit volume :
`p_(1)V_(1)=p_(2)V_(2)`
`therefore ("0.7 bar")(2.0 L)=(p_(2))(1L)`
`therefore p_(2)=(0.7xx2.0)/(1)` bar
`therefore p_(2)=1.4` bar `= p_(O_(2))`
where, At gas `O_(2)`
`p_(1)=0.7` bar
`V_(1)=2.0L`
`V_(2)=1.0L`
`p_(2)=(?)`
`p_("total")=p_(H_(2))+p_(O_(2))`
= 0.4 bar + 1.4 bar
= 1.8 bar
Discussion
24.

Which of the following act both as oxidising as well as reducing agents?

Answer»

`HNO_2`
`SO_2`
`H_2O_2`
`H_2S`

SOLUTION :`HNO_(2),SO _2and H_2O _2` ACT both as oxidising as WELL as REDUCING agents ...
Discussion
25.

Which of the following reactions will produce anisole?

Answer»

Phenol and METHYL chloride
Sodium PHENOXIDE and methyl chloride
Benzyl ALCOHOL and sodium chloride
None of the above

Solution :
Discussion
26.

The solubility product of SrF_(2)in water is 8xx10^(-10) Calculate its solubility in 0.1 M of aqueous NaF solution. If its solubility is expressed as y xx 10^(-8)then what is the value of 'y' ?

Answer»


Solution :` SrF_2hArr underset(S) Sr^(+2)+underset( 2S) (2F) ^(-) `
` [F^(-) ] " from " 0.1 M NAF " is "0.1 M`
TOTAL ` [F^(-) ] =0.1 +2S = (0.1 )^(2) `
` K_(sp)= S( 0.1) ^(2) rArr(8XX 10 ^(-10) )/( 10^(_2)) =SrArr S = 8 xx 10 ^(-8) `
Discussion
27.

What would be the IUPAC name and symbol for the element with atomic number 120 ?

Answer»

SOLUTION :Unbinlium, UBN
Discussion
28.

Toluene undergoes nitration easily than Benzene why?

Answer»

Solution :`(i)` Toluene has a methyl group on the benzene ring which is electron releasig group and hence activate the benzene ring by pushing the electrons on the benzene ring by pushing the electrons on the benzene ring.
`(ii)` `CH_(3)` group is ortho-paro director and ring ACTIVATOR. There fore in toluene, ortho and para positions are the most reactive towards an ELECTROPHILIC, THUS promoting electrophilic substiution reaction.
`(iii)` The methyl group hence makes it around `25` times more reactive than benzene.
`:.` it UNDERGOES nitration than benzene.
Discussion
29.

Which of the following is powerful reducing agent that used widely in organic chemistry ?

Answer»

`KalH_(4)`
`LiAlH_(4)`
`C_(5)H_(10)`
`NaAlH_(4)`

Answer :B
Discussion
30.

What is the electrophile when RCl + AlCl_3 are used in Friedel-Crafts reaction ?

Answer»

`CL^+`
`AlCl_4^-`
`R^+`
`AlCl_2^+`

ANSWER :C
Discussion
31.

Which one of the following expressions represent the electron probability function (D)

Answer»

`4pir" DR "PSI^(2)`
`4pir^(2)" dr "Psi`
`4pir^(2)" dr "Psi^(2)`
`4pir" dr "Psi`

ANSWER :C
Discussion
32.

Write the IUPAC names of the following compounds. (i) CH_(3)-underset(CHO)underset(|)(CH)-CH_(2)-CH_(2)-CH_(3) (ii) CH_(3)-CH_(2)-CH_(2)-underset(COOH)underset(|)(CH_(2))=CH-CH_(2)-CH_(3) (iii) CH_(3)-CH_(2)-underset(CH_(3))underset(|)(CH)-CH_(2)-CH_(2)CN

Answer»

SOLUTION :(i) PENTAN-2-al
(II) Pentan-(2-ene-2-propyl)-1-oic ACID
(III) 4-methyl-1-cyanohexane
Discussion
33.

Which one of the following statement is incorrect?

Answer»

`H_(2)` reacts with `Cl_(2)` to form HCl, an electron pair SHARED between H and Cl
Hydrogen is reduced by sodium toform NAH. An electron is tranferred from H to NA
Hydrogen REDUCES copper (II) oxide to cooper and itself gets oxidized to `H_(2)O`
Hydroformylation of olefins yields aldehyde which further undergoes reduction to GIVE alcohol.

Answer :B
Discussion
34.

Which out of NH_(3) and NF_(3) has higher dipole moment and why ?

Answer»

SOLUTION :The dipole moment of `NH_(3) ` is more than `NH_(3)`. Dipole moment of `NH_(3) = 1.47 D = 4.9 xx 10^(-30)` C m
Dipole moment of `NF_(3) = 0.23 D = 0.8 xx 10^(-30)` C m
`mu (NH_(3)) gt mu (NF_(3)) : ` Both the molecules have pyramida shape with a lone pair of electrons on nitrogen atom.

Electronegativity: H (2.1), N (3.0) and F (4.0) os, partially N NEGATIVE in `NH_(3)` but positive in `NF_(3)`. In case of `NF_(3)` the orbital dipole due to lone pair is in the same direction as the RESULTANT dipole moment of the N - H bonds where as in `NF_(3)` the orbital dipole is in the direction opposite to the resultant dipole moment of the three N - F bonds.
The orbital dipole because of lone pair decreases the effect of the resultant N - F bond moments. Which results i the low dipole moment of `NF_(3)` as represented below.
Discussion
35.

Which of the following respresents 2, 2, 3-trimethyl hexane?

Answer»

`CH_3 - C(CH_3)_2 - CH_2 - CH_2 - CH (CH_3)_2`
`CH_3 - CH (CH_3) - CH_2 - CH (CH_3) - CH_2 - CH_3`
`CH_3 - C(CH_3)_2 - CH(CH_3) - CH_2 - CH_2 - CH_3`
`CH_3 - C(CH_3)_2 - CH_2- C(CH_3)_2 - CH_3`

ANSWER :C
Discussion
36.

Viscosity of liquids decreases with increase of temprature. Why?

Answer»

Solution :VIscosity of liquids decreases as the temperature RISES because at high temperature MOLECULES have high kinetic ENERGY and can overcome the intermolecular forces to SLIP PAST one another between the layers.
Discussion
37.

What is the type of hybridisation of each carbon in the following compounds? (a) CH_(3)Cl (b) (CH_(3))_(2)CO (c ) CH_(3)CN (d) HCONH_(2) (e ) CH_(3)CH = CHCN

Answer»

SOLUTION :
`sp^(3)` carbon has FOUR single bond
`sp^(2)` carbon has one double bond
sp carbon has one TRIPLE bond or two double bond
Discussion
38.

The resonance effect of groups is electron removing (+R) or electron attracting (-R)?

Answer»

Solution :`+R` effect containing : In (a), `-OH` group, the MOLECULE push the ELECTRON away from it.
(-R) effect containing group: In (b) `-NO_(2)`, (C ) `-CHO` (d) -`CHO` (e ) `OVERSET(+)(C )H_(2)` and (F) `overset(+)(C )H_(2)`. These molecule attract the `pi` electron towards it
Discussion
39.

What is theuncertaintyDelta v . Delta xfor 1 mgobject? Whatin indicate ?

Answer»

SOLUTION :`Delta v . Delta X= (h)/( 4PI m) = (6.626 xx 10^(34) j s)/(4XX 3.1416xx 10^(6)kg )`
Thevalue of`Delta v. Delta x`obtainedextremely smalland isinsignificant.
Discussion
40.

Which among the following has zero dipole moment BF_(3),mH_(3),H_(2)O?

Answer»

SOLUTION :`BF_(3)`
Discussion
41.

Which reaction is not occuring in Solvay process ?

Answer»

`(NH_(4))_(2)CO_(3)+H_(2)O +CO_(2) to 2NH_(4)HCO_(3)`
`2KHCO_(3) overset(DELTA)to K_(2)CO_(3)+H_(2)O +CO_(2)`
`2NH_(4)Cl+Ca(OH)_(2) to 2NH_(3)+CaCl_(2)+H_(2)O`
`2NaHCO_(3) overset(Delta)to Na_(2)CO_(3)+H_(2)O+CO_(2)`

Answer :B
Discussion
42.

Which of the compounds with molecular formula C_5H_10 yields aceton on ozonolysis ?

Answer»

2-Methyl-1-butene
2-Methyl-2-butene
3-Methyl-1-butene
Cyclopentane

Answer :B
Discussion
43.

Which elements accept2e^(-) " or" 1e^(-)and from stable structure like noble gas ?

Answer»

Solution :Elements of group-16 accept 2e and form stable STRUCTURE and elements of group-17 accept `1E^(-)`and form stable structure because their electron NEGATIVITY ENTHALPY is more.
Discussion
44.

What are the conventions adopted in writing thermochemical equation?

Answer»

Solution :A thermochemical equation is a balanced stoichiometric chemical equation that includes the enthalpy change `(DeltaH)`.
Conventions adopted in thermochemical EQUATIONS:
(i) The coefficients in a balanced thermochemical equation REFER to number of moles of reacts and products involved in the reaction.
(ii) The enthalpy change of the reaction `DeltaH` has unit kJ.
(iii)When the chemical reaction is reversed, the value of All is reversed in sign with the magnitude
(iv)Physical states (GAS, liquid, aqueous and solid) of all species is important and must be SPECIFIED in a thermochemical reaction since `DeltaH` depends on the phases of reactants and products
(v) If the thermochemical equation is MULTIPLIED throughout by a number, the enthalpy change is also be multiplied by the same number value.
(vi) The negative sign of `DeltsH_(r)^(@)` indicates the reaction to be an exothermic and the positive sien of `DeltsH_(r)^(@)`indicates an endothermic type of reaction.
Discussion
45.

The group 1 metals of the periodic table of elements are collectively called alkali metals. Alkali metals are never found free in nature. Give reason.

Answer»

Solution :They are HIGHLY REACTIVE and hence do not OCCUR FREE.
Discussion
46.

Which combination cannot be used for the preparation of hydrogen gas in the laboratory ? I. Zinc/conc. H_(2)SO_(4) II. Zinc/dil. HNO_(3) III. Pure zinc/dil. H_(2)SO_(4)

Answer»

I and II
I,II,III
III only
I and III.

Solution :Zinc and conc. `H_(2)SO_(4)` given `SO_(2)` , zinc and dilute `HNO_(3)` gives `NH_(4)SO_(4)`. The reaction with PURE zinc and dil. `H_(2)SO_(4)` is very low.
Discussion
47.

Which of the following compounds will show tautomerism ?

Answer»

2,2-Dimethylpropanal
2,2-Dimethyl-1 nitropropane
Acetyl Acetone
Benzophenone

Solution :
Discussion
48.

Which of the following would produce effervescence with sodium bicarbonate ?

Answer»




All of these

Answer :D
Discussion
49.

What is nascent hydrogen?

Answer»

SOLUTION :Nascent HYDROGEN or 'just born hydrogen' is the hydrogen at the MOMENT of its GENERATION.
Discussion
50.

What is the significance of the word average in the definition of atomic mass ?

Answer»

Solution :The term AVERAGE in the definition of ATOMIC MASS signifies that the atomic mass of the GIVEN element is the average of atomic masses of all the known isotopes of that element in the RATIO of their occurrence in nature.
Discussion