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.

Predict giving reason the outcome of the reaction LiI + KF to

Answer»

Solution :`LiI + KF to LIF + KI` , larger CATION `(K^(+))` stabilizes larger anion `(I^(-))`.
Discussion
2.

Predict all the alkenes that would be formed by the dehydrohalogenation of the following halides with sodium ethoxide and identify the major alkene : (i) 2-Chloro-2-methylbutane (ii) 2, 2, 3-trimethyl-3-bromopentane (iii) Cyclohexylmethyl bromide (iv) 1-Bromo-1-methylcyclohexane

Answer»

Solution :(i) 2-Methylbut-2-ene (MAJOR) + 2-methylbut-1-ene (II) 3,4,4-Trimethylpent-2-ene (major) + 2,3,3-trimethylpent-1-ene
(III) 1-Methylcyclohexene (major) + methylene cyclohexane (IV) same as (iii)
Discussion
3.

Predict all the alkenes that would be formed by dehydrohalogenation of the following alkyl halides with sodium ethoxide in ethanol and identify the major alkene : (i)1-Bromo-1-methylcyclohexane,(ii)2-Chloro-2-methylbutane (iii)2,2,3-Trimethyl-3-bromopentane , (iv)

Answer»


ANSWER :`(##RES_CHM_ORM_IV_E01_009_A01##)`
Discussion
4.

Predict theposition of theelement in theperiodic tablesatisfyingthe electronic configuration(n-1) d^(1) ns^(2) " for " n=4

Answer»

Solution :Forn=4the ELECTRONIC CONFIGURATION = (4-1) `d^(1) 4s^(2) =3d^(1) 4s^(2)`. Theelementcorrespondingto this configurations is SCANDIUM whichis a d- blockelement.
Group number = NOOF electrons in (n-1) d subshell + No. of electrons in thenthshell = 1+2=3
Discussion
5.

Power alcohol is a mixture of petrol and alcohol in the ratio od

Answer»

`4:1`
`1:4`
`2:1`
`1:2`

SOLUTION :`4:1 ((80% + 20%),("Petrolalcohol"))`
Discussion
6.

ppi-ppioverlapping of C-atom with other elements is not effective when ...........

Answer»

the SIZE of ATOMIC ORBITAL is small.
the size of atomic orbital is big.
the size of atomic orbital is same.
the size of atomic orbital is same and big.

Answer :B
Discussion
7.

Potassium superoxide (KO_(2)) is used as a source of oxygen in submarines , space shuttles and in oxygen musks . How does it work ?

Answer»

SOLUTION :The moisture of the breath reacts with potassium superoxide `(KO_(2))` to LIBERATE `O_(2)` , and at the same time the KOH FORMED removes `CO_(2)` as it is EXHALED thereby allowing the atmosphere in the submarines , space shuttles and oxygen masks to be continuously REGENERATED .
`4 KO_(2) (s) + 2 H_(2)O (s) to4KOH (aq) + 3 O_(2)(g)`
`KOH (aq) + CO_(2) (g) to KHCO_(3)(s)`
Discussion
8.

Potassium superoxide finds use in breathing equipment and safeguards the use to breathe in oxygen generated internally in the apparatus without being exposed to toxic fumes outside. The supply of oxygen is due to(i) show decomposition of KO_(2)(ii) reaction of superoxide with moisture in the exhaled air (iii) reaction of KO_(2) with CO_(2) in the exhaled air.

Answer»

(i), (ii) and (iii) are correct
(ii) and (iii) are correct
(i) and (ii) are correct
(iii) is only correct

Solution :The moisture of the breath reacts with superoxide to liberate oxygen, andat the same TIME the potassium HYDROXIDE formed removes `CO_(2)` as it is EXHALED there by allowing the atmosphere in the equipment to be CONTINUOUSLY regenerated
`4KO_(2)(s) + 2H_(2)O(g) rarr4KOH(aq) + 3O_(2)(g)`
`2KO_(2)+2H_(2)Orarr2KOH+H_(2)O_(2)+O_(2)``KO_(2)` also continuously combines DIRECTLY with `CO_(2)` forming `K_(2)CO_(3)` and with `CO_(2)` and moisture together forming `KHCO_(3)`
`4KO_(2)+2CO_(2)rarr2K_(2)CO_(3)+3O_(2)`
`4KO_(2)+4CO_(2)+2H_(2)Orarr4KHCO_(3)+3O_(2)`
Discussion
9.

Potassium super oxide is preferred to sodium peroxide to purify air. Why?

Answer»

Solution :Air usually CONTAINS CARBON monoxide and carbondioxide pollutants. Sodium peroxide converts carbondioxide to oxygen, but it has no reaction with carbonmonoxide. POTASSIUM superoxide REACTS with both carbonmonoxide and carbondioxide GIVING oxygen. Hence `KO_(2)` is preferred over `Na_(2)O_(2)`.
Discussion
10.

Potassium permanganate is titrated against ferrous ammonium sulphate in acidic medium, the equivalent mass of potassium permanganate is :

Answer»

`("molecular mass")/(3)`
`("molecular mass")/(5)`
`("molecular mass")/(2)`
`("molecular mass")/(10)`

Solution :The ionic reaction involved in titration is :
`MnO_(4)^(-)+5Fe^(2+)+8H^(+) to MN^(2+)+4H_(2)O+5Fe^(3+)`
Since, a molecular of `KMnO_(4)` accepts 5 electrons in ACID medium, its EQUIVALENT mass will be `(("molecular mass")/(5))`.
Discussion
11.

Potassium permanganate acts as an oxidising agent in acidic, alkaline as well as neutral media. Which among the following statements is incorrect ?

Answer»

`N=M//5` (in ACID MEDIUM )
`N=M//3` (in ALKALINE medium)
`N=M//3` ( in NEUTRAL medium)
`N=M` ( in alkaline medium)

SOLUTION :N//A
Discussion
12.

Potassium permanganate oxidises oxalic acid in suphuric acid medium to give potassium sulphate, manganous sulphate, carbondioxide and water.

Answer»

Solution :(a) The SKELETON equation is written as
`KMnO_(4) +H_(2)C_(2)O_(4)+H_(2)SO_(4) to K_(2)SO_(4)+MnSO_(4)+CO_(2)+H_(2)O`
(b) Focusing on the oxidation numbers
`overset(+1)(K) overset(+7)(Mn) overset(-2)(O_(4))+overset(+1)(H_(2)) overset(+3)(C_(2)) overset(-2)(O_(4))+overset(+1)(H_(2)) overset(+6)(S) overset(-2)O_(4) to overset(+1)(K_(2)) overset(+6)(S) overset(-2)(O_(4)) + overset(+2)(Mn) overset(+6)(S) overset(-2)(O_(4))+overset(+4) (C) overset(-2)(O_(2)) +overset(+1)(H_(2)) overset(-2)(O)`
(c) Location atoms undergoing change in oxidation numbers.
`KM overset(+7)(n)O_(4)+H_(2) overset(+3)(C_(2))O_(4) to Mn overset(+2)(SO_(4))+C overset(+4)(CO_(2))`
(d) DETERMINE the change in oxidation numbers
(e) Cris- crossing these changes in oxidation numbers
`2KMnO_(4)+5H_(2)C_(2)O_(4) to MnSO_(4)+CO_(2)`
(f) Balancing the atoms other than hydrogen and oxygen
`2KMnO_(4)+5H_(2)C_(2)O_(4)+3H_(2)SO_(4) to K_(2)SO_(4)+2MnSO_(4)+10CO_(2)+H_(2)O`
(g) Balancing the atoms hydrogen and oxygen
`2KMnO_(4)+5H_(2)C_(2)O_(4)+3H_(2)SO_(4) to K_(2)SO_(4)+2MnSO_(4)+10CO_(2)+8H_(2)O`
This is the balanced EQUATIONS.
Discussion
13.

Potassium metal is heated strongly in O_(2). It produces

Answer»

`K_(2)O`
`K_(2)O_(2)`
`KO_(2)`
`KO`

ANSWER :C
Discussion
14.

Potassium metal is a better reducing agent that sodium but still potassium metal can be obtained by reduction of potassium chloride with sodium . How does it happen ?

Answer»

Solution :Potassium can be OBTAINED by reduction of KCl and Na vapours at 1125 K in a large fractionating column .
`KCl +Na overset(1125K)(to) NaCl + K`
This reduction occurs because the lattice energy of NaCl is higher `(-770 kJ mol^(-1))`than that of KCl `(-703 kJ mol^(-1)`) .
Discussion
15.

Potassium metal is - and then sodium?

Answer»

LIGHTER, SOFTER, more reactive
Heavier, softer, LESS reactive
Lighter, HARDER, more reactive
None of the above 

ANSWER :A
Discussion
16.

Potassium is used in photogalvanic cells. Why?

Answer»

Solution :Potassium is highly electropositive. Ionisation potential and work FUNCTION of potassium are LESS.
`KtoK^(+)+e^(-)` . The ionisation or separation of VALENCE electron of potassium is EASY.
Discussion
17.

Potassium gives a _________colour to the Bunsen flame

Answer»

VIOLET
blue
apple green
brick red

Solution :FLAME COLOUR of K is violet
Discussion
18.

Potassium dichromate (K_(2)Cr_(2)O_(7)) is an orange coloured compound, very frequently used in laboratory as an oxidising agent as well as in a redox titration. It is generally prepared from chromit (FeCr_(2)O_(4))ore according to the following reactions: (a) Fusion of chromite ore with sodium carbonate in excess of air. FeCr_(2)O_(4)+Na_(2)CO_(3)+O_(2) to Na_(2)CrO_(4)+Fe_(2)O_(3)+CO_(2) (b) Acidifying filetered sodium chromate solution with sulphuric acid. Na_(2)CrO_(4)+H_(2)SO_(4) to Na_(2)Cr_(2)O_(7)+Na_(2)SO_(4)+H_(2)O (c) Treating sodium dichromate with potassium chloride. Na_(2)Cr_(2)O_(7)+KCl to K_(2)Cr_(2)O_(7)+NaCl Answer the following questions using above information. If whole of the chromite ore given in the previous question gets consumed and sufficient amount of rest of the reactants are given, then the mass of K_(2)Cr_(2)O_(7) obtained is :

Answer»

14.7gm
7.35 gm
73.5gm
147gm

Answer :C
Discussion
19.

Potassium dichromate (K_(2)Cr_(2)O_(7)) is an orange coloured compound, very frequently used in laboratory as an oxidising agent as well as in a redox titration. It is generally prepared from chromit (FeCr_(2)O_(4))ore according to the following reactions: (a) Fusion of chromite ore with sodium carbonate in excess of air. FeCr_(2)O_(4)+Na_(2)CO_(3)+O_(2) to Na_(2)CrO_(4)+Fe_(2)O_(3)+CO_(2) (b) Acidifying filetered sodium chromate solution with sulphuric acid. Na_(2)CrO_(4)+H_(2)SO_(4) to Na_(2)Cr_(2)O_(7)+Na_(2)SO_(4)+H_(2)O (c) Treating sodium dichromate with potassium chloride. Na_(2)Cr_(2)O_(7)+KCl to K_(2)Cr_(2)O_(7)+NaCl Answer the following questions using above information. If you are intially provided with 224 gm of pure chromite ore and 169.6gm of sodium carbonate, the minimum volume of air required at 1 atm and 273 K to consume at least one of the reactant completely, if aire contains 20% by volume of oxygen gas is :

Answer»

156.8L
196L
28L
152.4L

Answer :a
Discussion
20.

Potassium dichromate (K_(2)Cr_(2)O_(7)) is an orange coloured compound, very frequently used in laboratory as an oxidising agent as well as in a redox titration. It is generally prepared from chromit (FeCr_(2)O_(4))ore according to the following reactions: (a) Fusion of chromite ore with sodium carbonate in excess of air. FeCr_(2)O_(4)+Na_(2)CO_(3)+O_(2) to Na_(2)CrO_(4)+Fe_(2)O_(3)+CO_(2) (b) Acidifying filetered sodium chromate solution with sulphuric acid. Na_(2)CrO_(4)+H_(2)SO_(4) to Na_(2)Cr_(2)O_(7)+Na_(2)SO_(4)+H_(2)O (c) Treating sodium dichromate with potassium chloride. Na_(2)Cr_(2)O_(7)+KCl to K_(2)Cr_(2)O_(7)+NaCl Answer the following questions using above information. If the number of moles of reactants available for reactions are: {FeCr_(2)O_(4)=0.25 moles, O_(2)=0.35 moles, Na_(2)CO_(3)=0.60 moles, H_(2)SO_(4)=0.2 mol,es, KCl=0.1 moles}, then the maximum number of moles of K_(2)Cr_(2)O_(7), that can be produced is :

Answer»

0.05 moles
0.1 moles
0.2moles
0.5moles

Answer :a
Discussion
21.

Potassium crystallizes with a

Answer»

face CENTRED CUBIC lattice
body centred cubic lattice
simple cubic lattice
ortho rhombic lattice

Solution :ALKALI metals crystallise as BCC LATTICES.
Discussion
22.

Potassium carbonate cannot be produced by Solvay process. Why?

Answer»

Solution :SOLVAY process cannot be EXTENDED to MANUFACTURE of POTASSIUM carbonate because potassium hydrogen carbonate is too soluble to be PRECIPITATED by the addition of ammonium hydrogen carbonate to a saturated solution of potassium chloride.
Discussion
23.

Potassium carbonate cannot be prepared by Solvay process. Why ?

Answer»

Solution :Potassium HYDROGEN carbonate (`KHCO_3`) is fairly soluble in water EVEN in the presence of EXCESS of carbon DIOXIDE and does not get PRECIPITATED. Hence, `K_2CO_3` cannot be prepared by Solvay process.
Discussion
24.

Potassium carbonate cannot be prepared by Solvay process. Why?

Answer»

SOLUTION :In Solvay.s PROCESS,initally `KHCO_3`will be FORMED which is more SOLUBLE and cannot be PRECIPITATED.
Discussion
25.

Potassium carbonate cannot be prepared by Solvay process . Why ?

Answer»

Solution :POTASSIUM carbonate cannot be prepared by Solvay PROCESS because potassium bicarbonate being more soluble than sodium bicarbonate does not get precipitated when `CO_(2)` is passed through a concentrated solution of KCl saturated with AMMONIA .
`KCl + CO_(2) + NH_(3) + H_(2)O to KHCO_(3) + NH_(4)CL`
Discussion
26.

Potash alum is used as a

Answer»

Disinfectant
WATER softner
MORDANT in textile industry
Fibre in POLYMER industry

Solution : POTASH ALUM is used as mordant and water softner
Discussion
27.

Possible structures of A is/are

Answer»




SOLUTION :
Discussion
28.

Possible oxidation states of boron family elements are

Answer»

`+1`
`+2`
`+3`
`+4`

SOLUTION :`+1, +3` (because of electronic CONFIGURATION `ns^(2)NP^(1)`)
Discussion
29.

Possible number of cyclic isomers for the compound having molecular formula C_(6)H_(4)Cl_(2) is ….. .

Answer»

6
4
5
3

Solution :
Discussion
30.

possible geometrical isomer are :

Answer»


SOLUTION :N//A
Discussion
31.

Possible enols in the reaction are ?

Answer»




SOLUTION :ALDOL CONDENSATION.
Discussion
32.

Positronium consists of an electron and a positron (a particle which has the same mass as an electron , but opposite charge ) orbiting round their common centre of mass. Calculate the value of the Rydberg constant for this system

Answer»

`R_oo //4`
`R_oo //2`
`2R_oo`
`R_oo`

ANSWER :B
Discussion
33.

Positive Tollens test Compound (A) is:

Answer»

`CH_(3)-overset(O)overset(||)C-underset(OCH_(3))underset(|)(CH-)underset(OCH_(3))underset(|)(CH_(2)`
`CH_(3)-overset(O)overset(||)C-underset(OCH_(3))underset(|)overset(OCH_(3))overset(|)(C-CH_(3)`
`CH_(3)-overset(O)overset(||)C-CH_(2)-underset(OCH_(3))underset(|)(CH)-OCH_(3)`
`H-overset(O)overset(||)C-CH_(2)-underset(OCH_(3))underset(|)(CH_(2)-CH-OCH_(3)`

SOLUTION :
Discussion
34.

Positive soil pollution is

Answer»

Reduction is soil productivity due to addition of PESTICIDES fertllizers and inductrial wastes
Reduction is soil productivity due to erosion and over USE :
Converting fertile LAND into BARREN land by dumping ash garbage and rubbish
None of these

Solution :Coverting fertile land into barren land by dumping ash, garbage and rubbish
Discussion
35.

Positive catalyst for the decomposition of H_2O_2 among the following

Answer»

Alcohol
Iron
Sodium-pyrophosphate
Urea

ANSWER :B
Discussion
36.

Positive and Negative electromeric effect

Answer»

SOLUTION :(a) NEGATIVE (-E) ELECTROMERIC effect (B) Positive (+E) electromeric effect
Discussion
37.

Portland cement is manufactured by using

Answer»

lime stone, CLAY and SAND
lime stone, GYPSUM and sand
lime stone, gypsum and alumina
lime stone, clay and gypsum.

Solution : lime stone, clay and gypsum.
Discussion
38.

Portland cement does not contain:

Answer»

`CaSiO_(4)`
`Ca_(2)SiO_(5)`
`Ca_(2)Al_(2)O_(6)`
`Ca_(3)(PO_(4))_(2)`

Answer :4
Discussion
39.

Portland cement clinker has highest weight percentage of

Answer»

DICALCIUM silicate
tricalcium silicate
dicalcium aluminate
tricalcium aluminate

Answer :B
Discussion
40.

Polythene is

Answer»

`(-H_(2)C=CH_(2)-)_(N)`
`(-HC=CH-)_(n)`
`(-H_(3)C=CH_(3)-)_(n)`
`(-H_(2)C-CH_(2)-)_(n)`

ANSWER :D
Discussion
41.

Polytetrafluoroethylene is commercially known as

Answer»

Teflon
Freon
Lewisite
Westron

Answer :A
Discussion
42.

Polyphosphates llike sodium hexametaphosphate (calgon) are used as water softening agents because they

Answer»

form soluble complexes with ANIONIC species
precipitate anionic species
form soluble complexes with CATIONIC species
precipitate cationic species.

Solution :Polyphosphates like sodium hexametaphosphate (calgon) form soluble complexes with cations like `Ca^(2+)` and `Mg^(2+)` present in HARD water and hence used as water SOFTENING agents.
`Na_(6)P_(6)O_(18)to 2NA^(+)+Na_(4)P_(6)O_(18)^(2-)`
`M^(2+)+Na_(4)P_(6)O_(18)^(2-)to [Na_(2)MP_(6)O_(18)]^(2-)+2Na^(+)`
Discussion
43.

Polyphosphates are used as water softening agents because they.....

Answer»

form soluble complex with ANIONIC species
precipitate anionic species
form soluble complex with CATIONIC species
precipitate cationic species

Answer :C
Discussion
44.

Polynuclear aromatic compound of the following is

Answer»

BENZENE 
Cyclopentadienyl ANION 
Phenanthrene
Cyclooctatetraene 

ANSWER :C
Discussion
45.

Polymers 'X' and 'Y' respectively are:

Answer»

nylon-6, nylon-6,6
nylon-6,6, nylon-6
nylon-6, nylon-6, 10
nylon-6,6, nylon-6,10

ANSWER :D
Discussion
46.

Polymers are made up of small molecules called monomers. Polymer which are formed by one type of monomer is called homopolymer and which are formed by more than one type of monomers are called co-polymers. Natural polymers are biodegradable whereas synthetic polymers may or may not be. Addition or chain growth polymerization involves the repeated addition of monomers to the polymer chain. The monomers are unsaturated compounds and this type of polymerization takes place by ionic (cationic or anionic) as well as free radical mechanism. Condensation or step growth polymerization involves a series of condensation reactions between twomonomers. Each monomer normally contains two functional groups. Branch chain polymers may be condensation or addition but cross linked polymers are always condensation polymers. Which one of the following polymers is prepared by condensation polymerization?

Answer»

DACRON
Teflon
Styrene
Rubber

Answer :A
Discussion
47.

Polymers are made up of small molecules called monomers. Polymer which are formed by one type of monomer is called homopolymer and which are formed by more than one type of monomers are called co-polymers. Natural polymers are biodegradable whereas synthetic polymers may or may not be. Addition or chain growth polymerization involves the repeated addition of monomers to the polymer chain. The monomers are unsaturated compounds and this type of polymerization takes place by ionic (cationic or anionic) as well as free radical mechanism. Condensation or step growth polymerization involves a series of condensation reactions between twomonomers. Each monomer normally contains two functional groups. Branch chain polymers may be condensation or addition but cross linked polymers are always condensation polymers. Which one of the following monomer is most reactive for anionic polymerization?

Answer»

`C_(6)H_(5)-CH=CH_(2)`
`C_(6)H_(5)-UNDERSET(C_(6)H_(5))underset(|)(C )=CH_(2)`
`CH_(3)-underset(CH_(3))underset(|)(C)=CH_(2)`
`H_(2)C=CH_(2)`

Answer :B
Discussion
48.

Polymers are made up of small molecules called monomers. Polymer which are formed by one type of monomer is called homopolymer and which are formed by more than one type of monomers are called co-polymers. Natural polymers are biodegradable whereas synthetic polymers may or may not be. Addition or chain growth polymerization involves the repeated addition of monomers to the polymer chain. The monomers are unsaturated compounds and this type of polymerization takes place by ionic (cationic or anionic) as well as free radical mechanism. Condensation or step growth polymerization involves a series of condensation reactions between twomonomers. Each monomer normally contains two functional groups. Branch chain polymers may be condensation or addition but cross linked polymers are always condensation polymers. Which one of the following is biodegradable polymer?

Answer»

Nuylon6,6
Glyptal
Cellulose
PVC

Answer :C
Discussion
49.

Polymers are made up of small molecules called monomers. Polymer which are formed by one type of monomer is called homopolymer and which are formed by more than one type of monomers are called co-polymers. Natural polymers are biodegradable whereas synthetic polymers may or may not be. Addition or chain growth polymerization involves the repeated addition of monomers to the polymer chain. The monomers are unsaturated compounds and this type of polymerization takes place by ionic (cationic or anionic) as well as free radical mechanism. Condensation or step growth polymerization involves a series of condensation reactions between twomonomers. Each monomer normally contains two functional groups. Branch chain polymers may be condensation or addition but cross linked polymers are always condensation polymers. Which of the following is a chain growth polymer?

Answer»

Polystryrene
PTFE
Polybutadiene
All of these

Answer :D
Discussion
50.

Polyethylene is a/an :

Answer»

RANDOM co-polymer
HOMOPOLYMER
ALTERNATE co-polymer
cross-linked co-polymer

ANSWER :B
Discussion