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.

Two reactions are given below: (i) H_(2)O(g)+(1)/(2)O_(2)(g) rarrH_(2)O(l) (ii) H_(2)(g)+(1)/(2)O_(2)(g) rarr H_(2)O(g) Which one will have greater value of DeltaH and why ?

Answer»

Solution :Reaction(i) will have greater value of `DELTAH`because when `H_(2)O(G)` CONDENSES to form`H_(2)O(l)` , some heatis EVOLVED( called heatof CONDENSATION).
Discussion
2.

What is basic difference between the terms electron gain enthalpy and electronegativity?

Answer»

Solution :ELECTRON gain enthalpy refers to TENDENCY of an isolated gaseous atom to accept an additional electron to FORM a negative ion. Whereas ELECTRONEGATIVITY refers to tendency of the atom of an element to attract shared pair of electrons towards it in a covalent bond.
Discussion
3.

What is diagonal relation? Give one pair of elements, that have this relation.

Answer»


ANSWER :elements of a GROUP and second PERIOD has similarity to NEXT group and next period element. EG. Li-Mg, Be-Al
Discussion
4.

The volume of CO_(2)that can be obtaind at STP from 60 g. of 70% pure MgCO_(3) is

Answer»

16L
11.2L
1.12L
5.6L

Solution :WEIGHT of pure `MgCO_(3)=(70)/(100)xx60=42g`
`MgCO_(3)rarrMgO=CO_(2)`
`84g ______ UNDERSET("22.4 L")underset(DARR)(44g)`
`42g______11.2L`
Discussion
5.

Which of the following is not common component of photochemical smog?

Answer»

Ozone
Acrolein
Perozyacetayl NITRATE
CHLOROFLUOROCARBONS

ANSWER :D
Discussion
6.

What will be the basicity of H_2BO_3, which is not a protic acid ?

Answer»

ONE
TWO
three
four

Discussion
7.

Write the detail about hydrogenation of unsaturates hydrocarbon.

Answer»

Solution :Defination of HYDROGENATION : Dihydrogen gas adds to alkenes and alkynes in the presene of finely divided catalysts like platinum, palladium or nickel to form alkanes. This process is called hydrogenation.
* Work of catalyst : These metals absorb dihydrogen gas on their surfaces and activate the hydrogen-hydrogen bond. Platinum and palladium CATALYSE the reaction at room temperature but RELATIVELY higher temperatureand pressure are REQUIRED with nickel catalysts.
* Some examples of hydrogenation reaction : When hydrogen is added to unsaturated hydrocarbons like alkene and alkyne and alkane is formed, such type of reaction is known as alkane.
(i) `underset("Ethene")(CH_(2))=CH_(2)+H_(2)underset(or Ni, Delta)overset(Pt//Pd)rarrunderset("Ethane")(CH_(3))-CH_(3)`
(ii) `underset("Propane")(CH_(3))-CH=CH_(2)+H_(2)underset(or Ni, Delta)overset(Pt//Pd)rarr underset("Propane")(CH_(3))-CH_(2)-CH_(3)`
(iii) `underset("PROPYNE")(CH_(3))-C-=C-H+2H_(2)underset(or Ni, Delta)overset(Pt//Pd)rarrunderset("Propane")(CH_(3))-CH_(2)-CH_(3)`
Note : Rany nickel is used as catalyst. It is a working nickel catalyst and used in the form of powder.
Discussion
8.

Which of the following is a characteristic feature of a free radical?

Answer»

It has a POSITIVE charge
It has a NEGATIVE charge
It has all PAIRED electrons.
It has an UNPAIRED electron.

Answer :D
Discussion
9.

Write history and devlopement of organic chemistry

Answer»

Solution :Science of organic chemistry is about two hundred years old. Berzillius: Berzillius, a Swedish CHEMIST proposed that v .vital force. was responsible for the formation of organic compounds.
1828: In 1828F, Wohler synthesised an organic compound, UREA from an inorganic compound, ammonium cyanate,
`UNDERSET("Ammonium cyanate")(NH_(4)CNO) overset("Heat")RARR underset("Urea")(NH_(2)CONH_(2))`
The pioneering synthesis of acetic acid by Kolbe (1845) and that of methane by BERTHELOT (1856) showed conclusively that organic compounds could be synthesised from inorganic sources in a laboratory.
Discussion
10.

Which of the following graphs correspond to one node-

Answer»




ANSWER :B
Discussion
11.

Which of the following is phenyl ethanoate ?

Answer»




ANSWER :A
Discussion
12.

The screening effect of inner electrons of an atom causes

Answer»

DECREASE in IONISATION energy
increase in ATOMIC size
increase in ionisation energy
decrease in atomic size

Answer :A::B
Discussion
13.

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»

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

Solution :`CuCl_(2)` gives a black precipitate with `S^(2-)` ions.
`Cu^(2+) + S^(2-) rarr underset(("Black ppt."))(CuS)`
`CuSO_(4)` formed remains soluble in AQUEOUS solution
Discussion
14.

What is the main limiatation of the first law of thermodynamics ?

Answer»

SOLUTION :It cannot PREDICT the SPONTANEITY of a PROCESS.
Discussion
15.

Which of the following statements is incorrect for PCI_5 ?

Answer»

Its all P-Cl bond lengths are equal
It involves SPID hybridisation
It has irregular geometry
Its SHAPE is TRIGONAL bipyramid

ANSWER :A
Discussion
16.

Which of the following is correct order of the stability of carbocations?

Answer»

`""^(+)CH_(3) GT""^(+)CH_(2)CH_(3) gt ""^(+)CH(CH_(3))_(2) gt ""^(+)C(CH_(3))_(3)`
`""^(+)CH_(2)CH_(3) gt""^(+)CH_(3) gt ""^(+)CH(CH_(3))_(2) gt ""^(+)C(CH_(3))_(3)`
`""^(+)C(CH_(3))_(3) gt ""^(+)CH(CH_(3))_(2) gt ""^(+)CH_(2)CH_(3) gt ""^(+)CH_(3)`
`""^(+)CH(CH_(3))_(2) gt ""^(+)CH_(3) gt ""^(+)CH_(2)CH_(3) gt ""^(+)C(CH_(3))_(3)`

Answer :C
Discussion
17.

Which of the following statements is incorrect in relation to ionization enthalpy?

Answer»

lonization ENTHALPY increases for each successive ELECTRON
The greatest increase in ionization enthalpy is experienced on removal of ELECTRONS from CORE noble gas configuration.
End of VALENCE electrons is marked by a big jump in ionization enthalpy
Removal of electron from orbitals bearing lowern value is easier than from orbital having high value.

Answer :D
Discussion
18.

The state of hybridization of C_(2), C_(3), C_(5) and C_(6) of the hydrocarbon is in the following sequence…… underset(7)(C )H_(3)- underset(underset(CH_(3))(6|))overset(overset(CH_(3))(|))(C )-underset(5)(C H)= underset(4)overset(overset(CH_(3))(|))(C )- underset(3)(C )H_(2)- underset(2)(C )-= underset(1)(C )H

Answer»

`SP, sp^(3), sp^(2) and sp^(3)`
`sp^(3), sp^(2), sp^(2) and sp`
`sp, sp^(2), sp^(2) and sp^(3)`
`sp, sp^(2), sp^(3) and sp^(2)`

ANSWER :A
Discussion
19.

Which forces of attraction are responsible for liquification of hydrogen chloride

Answer»

COULOMBIC FORCES
DIPOLE forces
hydrogen bonding
vander WAAL's forces

Solution :HCL has dipole forces .
Discussion
20.

Which one of the following is used as water softener?

Answer»

ZEOLITES
 lime
washing soda
bleaching powder

Answer :a
Discussion
21.

What are intersitials in a crystal ?

Answer»

Solution :Atoms or ions that FILL the NORMAL vacent intersitial VOIDS in a crystal are called interstitials.
Discussion
22.

Which of the following is a constituent of baking powder ?

Answer»

CREAM of TARTAR
Citric acid
Lactic acid
Glycerol

Solution :Cream of tartar
Discussion
23.

Which of the following are true ?

Answer»

In NaCl crystals , `Na^+` ions are present in all the OCTAHEDRAL voids
In ZnS (zinc blende) , `ZN^(2+)` ions are present in alternate tetrahedral voids .
In `CaF_2, F^- ` ions occupy all the tetrahedral voids
In `Na_2O, O^(2-)` ions occupy half the octahedral voids.

SOLUTION :Only (d) is not true because in `Na_2O, O^(2-)` ions are present in close packing and `Na^+` ions occupy all the tetrahedral voids.
Discussion
24.

The solubility product of Al (OH)_3 is 2.7 xx 10^(-11). Calculate the solubility in g L^(-1)and also find pH of this solution. (Atomic mass of Al = 27 u).

Answer»

SOLUTION :LET S be the solubility of `AL(OH)_3`
`{:(Al(OH)_3 hArr, Al_((aq))^(3+) + , 3OH_((aq))^(-)),(1,0,0),(1-s,s,3s):}`
Concentration to species at t=0
Concentration of various species at EQUILIBRIUM
`K_(sp)=[Al^(3+)] [OH^-]^3 =(S) (3s)^3 = 27S^4`
`S^4=K_(sp)/27=(2.7+10^(-11))/27=1xx10^(-12)`
`S=1xx10^(-3) "mol L"^(-1)`
(i) Solubility of `Al(OH)_3`
Molar mass of `Al(OH)_3` is 78 g. Therefore ,
Solubilityof `Al(OH)_3` in g `L^(-1)`
`=1xx10^(-3) xx 78 g L^(-1) 78xx10^(-3) g L^(-1)`
`=7.8xx10^(-2) g L^(-1)`
(ii) pH of the solution
`S=1xx10^(-3) "mol L"^(-1)`
`[OH^-]=3S=3xx1xx10^(-3)=3xx10^(-3)`
pOH=3-log 3
pH=14-pOH =11+log 3 = 11.4771
Discussion
25.

Write the resonance structures for Ozone molecule

Answer»

SOLUTION :OZONE MOLECULE `O_(3)` :
Discussion
26.

What is Visocity ?

Answer»

SOLUTION : ..Viscosity is a MEASURE of resistance to flow which arises due to the INTERNAL FRICTION between layers of fluid or they slip PART one another while liquid flows...
Discussion
27.

When 20 mL of (M)/(10) NaOH are added to 10 mL of (M)/(10)HCl, the resulting solution will :

Answer»

TURN blue litmus RED
turn phenolphthalein solution pink
turn methyl orange red
have no EFFECT on EITHER red or blue litmus

Solution :N//A
Discussion
28.

Water always flows from higher level to lower level on its own. Which of the following statement is correct for this phenomena ?

Answer»

FREE ENERGY increases
Entropy decreases
Free energy decreases
Entropy increases

Answer :C
Discussion
29.

.What are A,B,C and D in these conversions ?

Answer»

Solution :`BeO+C+Cl_(2) to BeCl_(2) +CO`
`BeCl_(2) +LiAlH_(4) to LiCl+AlCl_(3)+2BeH_(2)`
`BeCl_(2)+2H_(2)O to Be(OH)_(2)+2HCL`
`Be(OH)_(2) +2OH^(-) to [Be(OH)_(4)]^(2-)`
`A-BeCl_(2) , B - BeH_(2) , C-Be(OH)_(2) and D[Be(OH)_(4)]^(2-)`
Discussion
30.

Which of the following represents the composition of carnallite mineral ?

Answer»

`K_(2)O.Al_(2)O_(3).6SiO_(2)`
`KNO_(3)`
`K_(2)SO_(4).MgSO_(4).MgCl_(2).6H_(2)O`
`KCl.MgCl_(2)6H_(2)O`

SOLUTION :Carnallite mineral `KClMgCl_(2)*6H_(2)O`
Discussion
31.

Which one of the following is not electrophile?

Answer»

`NH_(3)`
`AICI_(3)`
`FeCI_(3)`
`R-X`

ANSWER :A
Discussion
32.

Write the value forCH_3COOH and NaCl .

Answer»

SOLUTION :` i_(CH_3 COOH)- 0.5 (CH_3 COOH "in " C_6H_6 ) `
` i_(NACL) -2 (NaCl "in " H_2O) `
Discussion
33.

The set representing the correct order of ionic radius is

Answer»

`LI ^(+) gt Be ^(2+) gt Na ^(+) gt Mg ^(2+)`
`Na ^(+) gt Li ^(+) gt Mg ^(2+) gt Be ^(2+)`
`Li ^(4+) gt Na ^(+) gt Mg^(2+) gt Be ^(2+)`
`Mg ^(2+) gt Be ^(2+) gt Li ^(+) gt Na ^(+)`

Solution :Ionic radius increases from top to bottom and DECREASES on MOVING from LEFT to right in a periodic table.
Discussion
34.

Which of the following metals rendered passive with Conc.HNO_(3)

Answer»

`Be`
`Na`
`Mg`
`BA`

Solution :BERYLLIUM metal is RENDERED with conceatrated `HNO_(3)` due to the FORMATION of protective oxide film LAYER of Beo.
Discussion
35.

Which hydride is called alante?

Answer»

`CaH_(2)`
`LiA//H_(2)`
`NaBH_(4)`
`A//H_(3)`

SOLUTION :`KiAlH_(4)` is called alanate.
Discussion
36.

Which of the following is/are +vely charged colloid

Answer»

`Al(OH)_(3)`
`SnO_(2)`
Haemoglobin
GOLD

Solution :(abc) `Al(OH)_(3),SnO_(2)` and haemoglobin are +vely charged due to adsorption of +ve CHARGE.
(d) Gold is -vely charged colloid due to capture of electrons in Bredig's Arc method.
Discussion
37.

Which of the following is electron deficient ?

Answer»

`PH_(3)`
`(CH_(3))_(2)`
`BH_(3)`
`NH_(3)`

SOLUTION :`NH_(3),PH_(3) - ` electron rich,
`CH_(3) - CH_(3) -` COVALENT neutral MOLECULE,
`BH_(3)` - electron deficient
Discussion
38.

Which of the following compounds possesses the C-H bond with the lowest bond dissociation energy ?

Answer»

TOLUENE
Benzene
n-Pentane
2, 2-Dimethylpropane

Solution :More stable the free radical formed upon homolytic fission of C-H bond, lesser is the bond dissociation energy. Since the stability of the radicals formed from toluene, benzene, n-pentane, 2, 2-dimethylpropane follows the order :
`C_(6)H_(5)OVERSET(*)(C)H_(2) gt (CH_(3))_(3)overset(*)(C) gt CH_(3)overset(*)(C)HCH_(2)CH_(2)CH_(3) gt overset(*)(C_(6))H_(5)`, therefore, the C-H bond of toluene has the LOWEST bond dissociation energy.
Discussion
39.

Writenotes on isomerisaton

Answer»

Solution :Isomerisatin is achemicalprocessby whicha compoundis transformedintoany toisomeric form
(ii)Normalalkanescan beconverted intobranched alkanesin THEPRESENT of `AiCI_(2)` ANDAT 298 K
(ii) Thisprocess is fogreatindustrialimportanehte quantityof gasolineisimprovesisomerisingtis components
Discussion
40.

Which important property did Mendeleev use to classify the elements in his periodic table and did he stick to that?

Answer»

SOLUTION :He classified elements according to atomic weight. He could`N^(+)` stick for this and he accept that physical and CHEMICAL PROPERTIES are basic for that.
Discussion
41.

Write structure of different isomers corresponding to the 5^(th) member of alkyne serie. Also awrite IUPAC names of all the isomers. What type of isomerism is exhibited by different pairs of isomers ?

Answer»

Solution :`5^(th)` member of alkyne has the molecular formula `C_(6)H_(10)`. It has seven possible alkaline isomers. The possible isomers are :
Position isomers :
(i) `underset("Hex-1-yne")(overset(6)(C)H_(3)-overset(5)(C)CH_(2)-overset(4)(C)H_(2)-overset(3)(C)H_(2)-overset(2)(C)-=overset(1)(C)H)`
(ii) `underset("Hex-2-yne")(overset(6)(C)H_(3)-overset(5)(C)H_(2)-overset(4)(C)H_(2)-overset(3)(C)-=overset(2)(C)-overset(1)(C)H_(3))`
(III) `underset("Hex-3-yne")(overset(1)(C)H_(3)-overset(2)(C)H_(2)-overset(3)(C)-=overset(4)(C)-overset(5)(C)H-overset(6)(C)H_(3))`
Chain isomers:
(iv) `underset("3-methylpent-1-yne")(H-overset(1)(C)-=overset(2)(C)-overset(3)(C)H_(2)-underset(CH_(3))underset(|)overset(4)(CH)-overset(5)(C)H_(3))`
(V) `underset("4-methylpent-1-yne")(Hoverset(1)(C)-=overset(2)(C)-underset(CH_(3))underset(|)overset(3)(CH)-overset(4)(C)H_(2)-overset(5)(C)H_(3))`
(vi) `underset("4-methylpent-2-yne")(H_(3)overset(1)-overset(2)(C)-=overset(3)(C)-underset(CH_(3))underset(|)overset(4)(CH)-overset(5)(C)H_(3))`
(vii) `underset("3,3-methylbut-1-yne")(H-overset(1)(C)-=overset(2)(C)-underset(CH_(3))underset(|)overset(CH_(3))overset(|)(C)-overset(4)(C)H_(3))`
Different isomers pairs have position and chain isomers.
Discussion
42.

What are the properties of electromagnetic radiations?

Answer»

Solution :(a) The radiant energy is emitted from any source continuously in the form of radiations (or) waves. Radiation is the EMISSION and transmission of energy through space in the form of waves.
(b) The electromagnetic waves consist of oscillating ELECTRIC and magnetic fields. These two filed components have the same wavelengths and frequency and travel in planes PERPENDICULAR to each other and also perpendicular to the direction of propagation of electromagnetic wave.
(c) The electromagnetic waves do not require any material medium for their propagation. They can travel in vacuum also.
(d) All electromagnetic radiations travel with the same velocity, namely, with the velocity of light `(3XX 10^(8) ms^(-1))`
(E) The electromagnetic radiations consist of difterent radiations which differ in their wavelength (or frequencies) and constitue "electromagnetic spectrum". Visible light is a small portion of electromagnetic spectrum.
Discussion
43.

The solid state of matter is converted inot gas by

Answer»

SUBLIMATION
deposition
FREEZING
condensation

ANSWER :A::B
Discussion
44.

What electronic transition in Li^(2+) produces the radiation of the same wave length as the first line in the Lyman series of hydrogen?

Answer»

N = 4 to n = 2
n = 9 to n = 6
n = 9 to n = 3
n = 6 to n = 3

Solution :`bar(upsilon) = Z^2 R [ 1/(n_1^2) - 1/(n_2^2)]` and E = `hc bar(upsilon)`
`""Li^(2+) ""H`
`(3)^2 (1/(n_1^2) - 1/(n_2^2)) = (1)^2 (1/((1)^2) - 1/((2)^2))`
on solving`n_1 =2 , n_2 = 4`
Discussion
45.

Which of the following salt is not obtained from lithium and magnesium ?

Answer»

Oxide
Bicarbonate
Nitride
Hydroxide

Answer :B
Discussion
46.

Which of the following species acts as Bronsted base but not as acid ?

Answer»

`CH_3COOH`
` HCO_3^(-)`
` H_2PO_2^(-)`
` H_2PO_3^(-)`

SOLUTION :` H_2PO_2^(-) `cannot LOSE ` H^(+) `
Discussion
47.

When the first element of the periodic table is treated with dioxygen , it gives a compound whose solid state floats on its liquid state. This compound has an ability to act as an acid a well as a base. What product will be formed when this compound undergoes autoionisation ?

Answer»

Solution :The first element of the periodic table is H and its molecular FORM is dihydrogen `(H_(2))` . When dihydrogen reacts with dioxygen , water is formed. Water is a liquid at room temperature . When liquid water freezes,it expnads to form ice . In other words, density of ice is lower than that of liquid wter and hence ice floats over water.
Water is amphoteric in nature, i.e., it acts as an ACID in presence of strong bases and a base in presence of strong acids.
`UNDERSET("Acid"_(1))(H_(2)O(l))+ underset("Base"_(2))(NH_(3)(aq)) to underset("Acids"_(2))(NH_(4)^(+)(aq))+ underset("Base"_(1))(OH^(-)(aq))`
`underset("Base"_(1))(H_(2)O(l))+ underset("Acid"_(2))(H_(2)S(aq)) to underset("Acids"_(1))(H_(2)O^(+)(aq))+ underset("Base"_(2))(HS^(-)(aq))`
Due to amphoteric CHARACTER, water undergoes self ionization as shown below :
`underset("Acid"_(1))(H_(2)O(l))+ underset("Base"_(2))(H_(2)O("base")) to underset("(CONJUGATE acid)")underset("Acids"_(2))(H_(3)O^(+)(aq))+ underset("(Comjugate base)")underset("Base"_(2))(OH^(-)(aq))`
This self ionization of water is called auto-protolysis.
Discussion
48.

Which of the following pairs of species have the same bond order-

Answer»

`O_(2),NO^(+)`
`CN^(-),CO`
`N_(2),O_(2)^(+)`
`CO,NO`

Solution :TOTAL no. of electrons PRESENT in `CN^(-)=14`
Total no. of electrons present in `CO=14`
MO electronic configuration of `CO-`
`(sigma_(1s))^(2)(sigma_(1s)^(**))^(2)(sigma_(2s))^(2)(sigma_(2p_(z)))^(2)(sigma_(2s)^(**))^(2)(pi_(2p_(X)))^(2)(pi_(2p_(y)))^(2)`
MO electronic configuration of `CN^(-)`-
`(sigma_(1s))^(2)(sigma_(1s)^(**))^(2)(sigma_(2s))^(2)(sigma_(2s)^(**))^(2)(pi_(2p_(x)))^(2)(pi_(2p_(y)))^(2)(sigma_(2p_(z)))^(2)` ltbgt bond order of `CO=(1)/(2)(8-2)=3`
Bond order of `CN^(-)=(1)/(2)(8-2)=3`
Discussion
49.

Which compound is 2,2,3-trimethyl hexane?

Answer»

`CH_(3)- underset(CH_(3))underset(|)overset(CH_(3))overset(|)C-overset(CH_(3)) overset(|) CH-CH_(2)-CH_(3)`
`CH_(3)- underset(CH_(3))underset(|) overset(CH_(3))overset(|)C- CH_(2)- overset(CH_3)overset(|)CH-CH_(3)`
`CH_(3)- underset(CH_3)underset(|)overset(CH_(3))overset(|)C-overset(CH_(3))overset(|)CH -CH_(2)- CH_(2)- CH_(3)`
`CH_(3) -underset(CH_3)underset(|)overset(CH_(3))overset(|)C-CH_(2) - CH_(2) - underset(CH_3)underset(|)overset(CH_3)overset(|)C-CH_(3)`

ANSWER :C
Discussion
50.

What weight of zinc would be required to produce enough hydrogen to reduce completely 7.95 g of CuO.

Answer»

Solution :The corresponding equations are :
`underset(65.38 g)(Zn) + H_(2)SO_(4) to underset(2.016 g)(ZnSO_(4)) + H_(2)`
and `underset(79.55 g)(CuO) + H_(2) to underset(2.016 g)(Cu) + H_(2)O`
`therefore 79.55 g` of CuO REQUIRE for REDUCTION, hydrogen = 2.016 g.
`therefore 7.95 g` of CuO will require for reduction, hydrogen `=(2.016)/(79.55) xx 7.95 = 0.201 g`
Moreover, `therefore 2.016 g` of `H_(2)` is produced by ZINC = 65.38 g
`therefore 0.201` g of `H_(2)` will be produced by zinc `=(65.38)/(2.016) xx 0.201 = 6.52 g`
Hence, the amount of zinc required to REDUCE 5 g of CuO is 6.52 g
Discussion