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.

Mass defect in the nuclear reactions may be expressed in terms of the atomic masses of the parent and daughter nuclides in place of their nuclear masses. The mass defect of the nuclear reaction: ._(5)B^(8) rarr ._(4)Be^(8)+e^(+) is

Answer»

`Deltam=at` mass of `._(5)B^(8)-at` mass of `._(4)Be^(8)`
`Deltam=at` mass of `._(5)B^(8)-at` mass of `._(4 )Be^(8)-` mass of one ELECTRON
`Deltam=at` mass of `._(5)B^(8)-at` mass of `._(4)Be^(8)+` mass of one electron
`Deltam=at` mass of `._(5)B^(8)-at` mass of `._(4)Be^(8)-` mass of TWO electrons

Answer :D
2.

Mass and energy are conserved. It is demonstrated by ___________ .

Answer»

FIRST LAW of thermodynamics
law of CONSERVATION of energy
law of conservation of mass
modified FORM of `1^(st)` law of thermodynamics

Answer :D
3.

Mass and energy are conserved is demonstrated by

Answer»

first law of thermodynamics
law of CONSERVATION of energy
law of conservation of MASS
modified form of Ist law of thermodynamics

Solution :In modified form of Ist law of thermodynamics, mass and energy both are CONSERVED.
4.

Marshall's acid overset(H_(2)O) to A+B Aoverset(H_(2)O)toB+C If P and Q represent maximum number of atoms that can lie in a plane of compound A and C respectively. Then, find out value of (P-Q).

Answer»


Solution :`UNDERSET("Marshall's acid")(H_(2)S_(2)O_(8))+H_(2)O to underset((A))(H_(2)SO_(5))+underset((B))(H_(2)SO_(4))`
`underset((A))(H_(2)SO_(5))+H_(2)O to underset((C))(H_(2)O_(2))+underset((B))(H_(2)SO_(4))`

P=5
Q=3
P-Q=5-3=2
5.

Marshall's acid (H_(2)S_(2)O_(8)) or peroxodisulphuric acid is prepared by the electrolytic oxidation of mmolH_(2)SO_(4) as : 2H_(2)SO_(4) rarr H_(2)S_(2)O_(8)+2H^(o+)+2e^(-) O_(2)(g) and H_(2)(g) are obtained as byproducts. In such electrolysis 4.48L of H_(2)(g) and 1.12L or O_(2)(g) were produced at STP. The weight of H_(2)S_(2)O_(8) formed is a. 9.7g""b.19.4g""c.14.5g""d.29.1g

Answer»

Solution :`b.` Refer Section `(point h)`.
Aqueous `UNDERSET((dil or conc))(H_(2)SO_(4)) overset(El ectrolysis)rarr2H^(o+)+SO_(4)^(2-)`
At anode, two reactions are COMPETING `:`
`i. 2SO_(4)^(2-) rarr S_(2)O_(8)^(2-)+2e^(-)`
`ii. H_(2)O rarr (1)/(2)O_(2)+2H^(o+)+2e^(-)`
At cathode, only one reaction occurs `:`
`2H^(o+) (` from `H_(2)SO_(4)) +2e^(-) rarr H_(2)(g)`
SINCE onereaction at cathode and two reactions at anode are taking place, therefore, the EQUIVALENT of `H_(2)(g)` produced at cathode at cathode should be equal to the equibalent of `O_(2)(g)` produced `+` equivalent of `H_(2)S_(2)O_(8)` formed.
`:.` Equivalent of `H_(2)=`Equivalent of `O_(2)+` Equivalent of `H_(2)S_(2)O_(8)`
`(4.48)/(22.4//2)=(1.12)/(22.4//4)+(W_(H_(2)S_(2)O_(8)))/(194//2)`
`0.4=0.2+(W)/(97)`
`:. W_(H_(2)S_(2)O_(8)=19.4g`
6.

Marshall's acid is used for laboratory preporations of :

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`H_2O `
` D_2O `
`D_2O_2`
HDO

ANSWER :C
7.

Marshall.s acid is,

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`H_2S_2O_5`
`H_2S_2O_8`
`H_2SO_3`
`H_2SO_5`

ANSWER :B
8.

Marsh test is applied for the detection of

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N
P
As
S

Answer :C
9.

Marsh gasmainlycontains :

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`C_(2)H_(2)`
`CH_(4)`
`H_(2)S`
CO

Answer :B
10.

Markownikoff's rule provides guidance of addition of HX on

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

Solution :Markownifkoffs RULE takes place inasymmetrical compound COMPOUNDS (C) is asymmetrical compound.
11.

Marsh gas mainly contains _____ . (H_2S, CO, C_2H_2, CH_4)

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METHANE
Ethane
Propane
Butane

Answer :A::C::D
12.

Markownikoff's rule governs the addition of

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ASYMMETRICAL reagent to symmetrical alkenes
symmetrical reagent to asymmetrical alkenes
asymmetrical reagent to asymmetricalalkenes
symmetrical REAGNET to symmetrical alkenes

ANSWER :C
13.

Markownikoff rule provides guidance of addition of HBr

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`CH_2=CH_2`
`CH_3-CH_2-CH_3`
`CH_3CH=CHCH_3`
`CH_2=CHBr`

Solution :
According to MARKOWNIKOFF's rule H atom or POSITIVE part GOES to that CARBON atom which more hydrogenated
14.

Markovnikov's rule governs the addition of

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UNSYMMETRICAL REAGENTS to SYMMETRICAL ALKENES
symmetrical reagents to unsymmetrical alkenes
unsymmetrical reagents to unsymmetrical alkenes
symmetrical reagents to symmetrical alkenes.

Answer :C
15.

Mark the wrong statement. Carbon differs from other elements due to :

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its ABILITY to form multiple bonds
its TENDENCY to catenation
its ability to extend its octet.
its tendency to form ring compounds.

Answer :A
16.

Mark the wrong statement. Halogens are all coloured

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This is DUE to absorbption of visible light by their molecules resulting in the excitation of outer electrons to higher ENRGY levels.
The small `F_2` molecules ABSORBS high energy violet radiations and appear light yellow in colour
The small `F_2`molecule absorb low energy yellow and green radiations and appear violet in colour
The excitation energy required by the small fluroine ATOMS is SMALLER than required by the large iodine atom

Answer :D
17.

Mark the wrong statement about H_2SO_4 .

Answer»

It acts as a reducing agent
It acts as a OXIDISING agent
It acts as dehydrating agent
It is less VISCOUS than WATER.

Solution :It acts as a reducing agent
It is less viscous than water.
18.

Mark the wrong statement among the following. The iron ore after washing is roasted with a little coal in excess of air. During roasting

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moisture is REMOVED
S and As are removed in the form of their volatile oxides
Any ferrous oxide is oxidised to femric wride
The mass becomes compact and THUS MAKES it suitable for READY REDACTION to metallic iron.

Answer :D
19.

Mark the wrong statement about enzymes

Answer»

Enzymes are highly specific both in BINDING chiral substrates and in catalysing their reactions
Each enzyme can catalyse a number of SIMILAR reactions.
Enzymes catalyse chemical reaction by lowering the energy of activation
Enzymes are NEEDED only in very small amounts for their ACTION.

ANSWER :B
20.

Mark the wrong statement about denaturation of proteins

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The primary structure of the protein does not change
Globular proteins are CONVERTED into fibrous proteins
Fibrous proteins are converted into globular
The BIOLOGICAL ACTIVITY of the protein is cancelled

Answer :D
21.

Mark the wrong staement among the following. The iron ore after washing is roasted witha little coasl in excess of air. During roasting

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Moistuyre is removed
As and S are removed in the form of their VOLATILE oxides
Any FERROUS oide is oxidised to ferric oxide.
The MASS becomes compact and THUS makes it sutiable for ready REDUCTION to metallic iron.

Answer :D
22.

Mark the variety of iron which has highest melting point

Answer»

PIG iron
Cast iron
Wrought iron
Steel

Answer :C
23.

Mark the strongest acid

Answer»

HF
HCl
HBr
Hl

Solution :HI is STRONGEST acid because H-I bond is WEAKEST AMONG HALOGEN acids.
24.

Markthe incorrentstatements.

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Catalyst PROVIDES an alternative pathway to REACTION mechanism
Catalyst raise theactivationenergy
Catalyst lowersthe activation ENERGY
Catalyst alters enthalpy CHANGE of thereaction

Solution :Function of Catalyst As the catalyst is added to the reaction medium rate of reation increases by decreasing activation energy of molecule. Hence, it follows an alternative pathway.
Catalyst does not change the enthalpy change of reaction. Energy of reactant and product remain same in both catalysed and UNCATALYSED reaction.
Hence, (a) and (d) are incorrect statements.
25.

Mark the steel in which carbon % is highest

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MILD steel
Hard steel
Alloy steel
None of these

Answer :B
26.

Mark the incorrect statements:

Answer»

CATALYST provides an alternative pathway to reaction mechanism.
Catalyst RAISES the activation energy.
Catalyst lowers the activation energy.
Catalyst ALTERS ENTHALPY change of the reaction.

ANSWER :C::D
27.

Mark the incorrect used of the polymer.

Answer»

HIGH density POLYTHENE - Buckets , pipes
Nylon 6,6 -Ropes , bristles for BRUSHES
Orlon - Synthetic WOOL , carpets
Glyptal -Electrical switches , combs

Solution :Glyptal is USED in manufacture of paints and lacquers.
28.

Mark the incorrect statements.

Answer»

Catalyst provides an ALTERNATIVE PATHWAY to reaction MECHANISM.
Catalyst raises the activation ENERGY.
Catalyst lowers the activation energy.
Catalyst not alters ENTHALPY change of the reaction.

Answer :A
29.

Mark the incorrect statement (s).

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Potassium dichromateoxidises a secondaryalcoholinto a ketone .
Potassium permangante is a weaker oxidisingagent than potassiumdichromate.
Potassiumdichromateoxidises a secondary alcohol intoaldehyde.
Alkaline `KMnO_(4)` SOLUTION oxidises tertiaryalcohol to a mixture of a ketoneand an acid.

Solution :In acidie medium , ` KMnO_(4)`gives 5 oxygenwhileacidic ` K_(2)Cr_(2)O_(7) ` gives 3 oxygen. `K_(2)Cr_(2)O_(7)`oxidisessecondaryalcohols to KETONES.
Tertiary alcohols are resistanceto oxidation in NEUTRAL or alkaline`KMnO_(4)`solutionbut are readilyoxidisedin acidic solution ` (KMnO_(4)//H_(2)SO_(4))` to a mixtureof a ketoneand an acid eachcontaininglessernumber of carbonatomsthan theoriginalalcohol.
30.

Markthe incorrect statement (s) for fuel cell

Answer»

it is USED in pollo space programme and for drinking water supply for astronauts
gydrogen and oxygen are bubbled through porous carbon electrode
catalyst like FINELY DIVIDED pt or pd are incorporated in to electrode
anode reaction is
`O_(2)2H_(2)O(l)+4e^(-)rarr4OH^(-)(aq)`

Solution :`H_(2)-O_(2)`fuel cell is usedover ordinary cell becausethey do not cause any pollutionand have high efficiencyof 60 - 70 %
31.

Mark the incorrect pair from the following.

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Schottky defect- Equal number of cations and anions are missing
Frenkel defect - Dislocation of cation from its normal site to an interstitial site
Impurity defect- `CdCl_2` in AgCl CRYSTAL to create CATIONIC vacancy
METAL EXCESS defect - `Fe_(0.93)O`

Answer :D
32.

Mark the incorrect example.

Answer»

KERATIN and myosin-Fibrous PROTEINS
Insulin and albumins -GLOBULAR proteins
Glycylalanine-Dipeptide
ENZYMES and haemoglobin -Derived proteins

Solution :Enzymes and haemoglobin are the examples of globular proteins.
33.

Mark the incorrect statement.

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Copper is EXTRACTED by SMELTING in a reverberatory furnace.
Zinc is extracted by reduction of OXIDE with aluminium .
Aluminium is extracted by electrolysis of its oxide.
Iron is extracted by reduction of its oxide in BLAST furnace.

Solution :ZICE is extracted by reduction of oxide with coke.
34.

Mark the gas which turns lime water milky

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`H_(2)S`
`SO_(2)`
`Cl_(2)`
`CO_(2)`

SOLUTION :`CO_(2) and SO_(2)` turns LIME WATER milky, as
`Ca(OH)_(2)(aq.)+CO_(2)tounderset(("milky"))(CaCO_(3))darr+H_(2)O`
`Ca(OH)_(2)+SO_(2)tounderset(("milky"))(CaSO_(3))darr+H_(2)O`
35.

Mark the halogen which shows electropositive character:

Answer»

F
Cl
Br
I

Answer :D
36.

Mark the element which shows only one oxidation state

Answer»

F <BR>CL
Br
I

ANSWER :A
37.

Mark the correct statement (s). (1) Manganese exhibits +7 oxidation state (2) Zinc forms coloured ions (3)[CoF_(6)]^(3-) is diamagnetic (4) Sc forms +4 oxidation state (5) Zn exhibits only +2 oxidation state.

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1 and 2
1 and 5
2 and 4
3 and 4

Solution :Both these STATEMENTS are correct
38.

Mark the correct statements out of the following

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He has highest `IE_(1)` in the periodic table.
CL has the highest EA out of all ELEMENTS in the periodic table.
Hg and Br are LIQUID at room temperature.
In any period, the atomic RADIUS of the NOBLE gas is lowest.

Answer :A::B::C
39.

Mark the correct statements about halogens.

Answer»

Electron AFFINITY of halogens is in the order `F gt Clgt Brgt I`.
HF is the STRONGEST hydrohalic acid.
`F_(2)` has lower bond dissociation energy than `Cl_(2)`
All halogens show VARIABLE OXIDATION states.

Solution :`F_(2)` has lower bond dissociation energy than `Cl_(2)` due to its SMALL size which results in interelectronic repulsion.
40.

Mark the correct statements out of the following:

Answer»

`He` and the highest `I.E_(1)` in the periodic table
`Cl` has the highest `E.A.` out of all the elements in the periodic table
`Hg` and `Br` are LIQUID at room temperature
In anyperiod, the ATOMIC radius of the NOBLE gas is lowest

Solution :Elements (a), (b) and (C) are correct. Statement (d) is incorrect as in any period, the atomic radius of the noble gas is largest.
41.

Mark the correct statements(s) (1) Manganeses exhibits +7 oxidation state (2) Zinc forms coloured ions (3) [CoF_(6)]^(3-) is diamagnetic (4) Sc forms +4 oxidation state (5) Zn exhibits only +2 oxidation state

Answer»

(i) and (II)
(ii) and (IV)
(III) and (iv)
(i) and (V)

ANSWER :D
42.

Mark the correct statements:

Answer»

Hg forms an AMALGAM with iron
Hg vapour is non-poisonous
Hg is MONO atomic and MONOVALENT in mercurous compound
Oxysalts of MERCURY are thermally unstable

Answer :D
43.

Mark the correct statement about thiokol rubber .

Answer»

It is a SYNTHETIC POLYSULPHIDE RUBBER
It is OBTAINED by condensation of ethylene chloride with sodium tetrasulphide
It is resistant to oils and abrasion
All are CORRECT

Solution :Properties of thiokol rubber .
44.

Mark the correctstatement

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METHYL AMINE isslightlyacidic
methyl amineisless basicthanammonia
methylamineis morebasicthanammonia
methyl amineformsaltwithalkalies

ANSWER :C
45.

Mark the correct statement

Answer»

Methyl amine is slightly acidic
Methyl amine is LESS basic than `NH_(3)`
Methyl amine is stronger base than `NH_(3)`
Methyl amine FORMS salts with alkalies

Solution :Presence of ALKYL group INCREASE electron density on nitrogen atom due to +I effect. Thus basic nature increases.
46.

Mark the correct relationship between the boiling points of very dilute solutions of BaCl_(2)(t_(1)) and LCl(t_(2)) ,having the same molarity

Answer»

`t_(1)=t_(2)`
`t_(1)gt t_(2)`
`t_(2)gt t_(1)`
`t_(2)` is approximately EQUAL to `t_(1)`

Solution :`BaCl_(2)` furnishes more ions than KCL and thus shows higher BOILING point `T_(1)gt T_(2)`.
47.

Mark the compound which turns black with NH_(4)OH

Answer»

Lead chloride
Mercurous chloride
Mercuric chloride
Silver chloride

Solution :`Hg_(2)Cl_(2)+2NH_(2)OH to NH_(2)-Hg-CL+underset(("BLACK ppt"))(Hg)`
48.

Mark the compound which turns black with NH_4 OH

Answer»

LEAD CHLORIDE
mercurous chloride
MERCURIC chloride
silver chloride

Solution :
49.

Mark the axymmetric carbon atoms and give the number of optical isomers in the following compounds: (i) CH_(3)-(CHOH)_(2)-COOH (ii) HOCH_(2)-(CHOH)_(4)-CHO (iii) HOCH_(2)-(CHOH)_(4)-CH_(2)OH

Answer»

Solution :
the compound cannot be divided into equal HALVES and it consists of two ASYMMETRIC carbon atoms
Hence, the NUMBER of d- and il-(optically active ) isomers,
`a=2^(n)=2^(2)=4`
and Number of meso forms, m=0
So, Total optical isomers `=a+m-4+0=4`


Where, `n=4,a=2((4-1))-2^(3)=8,m=2^((4//2-1))=2^((2-1))=2`.
`r=(8)/(2)=4`
So, Total optical isomers =8+2=10
50.

Mark the compound which gives carbon with conc. H_(2)SO_(4):

Answer»

formic acid
succinic acid
oxalic acid
SUGAR

Solution :`C_(12)H_(22)O_(11)overset("CON. "H_(2)SO_(4))to 12C+11H_(2)O`