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.

Which compound does not contain sp^(3) hybridised boron ?

Answer»

Product of the reaction of `H_(3)BO_(3)` and aqueoys SOLUTION of sodium HYDROXIDE
Borax
`1 : 1` ADDUCT of `BF_(3)` nd `NH_(3)`.
BORIC acid

Answer :D
Discussion
2.

What properties of water make it useful as a solvent ? What type of compounds can it (i) dissolve (ii) hydrolyse ?

Answer»

Solution :(i) Waterhas a high dielectric constant(79.39) and high DIPOLE moment (1.84D) . Because of these properties, water dissolves most of the inorganic (ionic) compounds and MANY covalent compounds. That is why water is called a UNIVERSAL solvent. Whereas ionic compounds dissolve in water due to iondipole interaction or solvation of ions, covalentcompounds such as alcohols, amines, urea, glucose, sugar, etc. dissolve in water due to H-bonding.
(ii) Water can hydrolyse many oxides (metallic or non-metallic ), hydrides, carbides, nitrides, phosphides and other salts. In these reactions , `H^(+)` and `OH^(-)` ions of water interact with anions and cations respectivity leading to the formation of an acid or a base or both as shown below :
`CaO(s) +H_(2)O(l) to Ca(OH)_(2)(aq)`
`SO_(2)(g) + H_(2)O (l) to H_(2)SO_(3)(aq)`
`CaH_(2)(s) + 2H_(2)O (l) to Ca(OH)_(2)(aq) + 2H_(2) (g)`
`CaC_(2)(s) + 2H_(2)O (l) to Ca(OH)_(2)(aq) + UNDERSET("Acetylene")(HC -=CH(g))`
Discussion
3.

Which of the following oximes is expected to exhibit both geometrical and optical isomerism

Answer»




SOLUTION :
Discussion
4.

The reagent used to detect fluoride present in water in

Answer»

ALUM + CAO + `CaOCl_2`
defluoron - I & II
ZIRCONIUM - ALIZARIN - S- dye
calcium aluminium fluoride

Answer :C
Discussion
5.

Why are Bohr's orbits called stationary states?

Answer»

SOLUTION :This is because the energies of the ORBITS in which the electrons REVOLVE are FIXED.
Discussion
6.

Which of the following is not used in writing electronic configuration of an atom?

Answer»

AUFBAU principle
Hund's rule
Pauli's EXCLUSION principle
Heisenberg's UNCERTAINTY principle

Answer :d
Discussion
7.

Which of the following statements are not true ?

Answer»

An element with BCC structure has TWO atoms PER unit cell.
An ionic COMPOUND `A^+ B^-` with BCC structure has one AB formula unit per unit cell.
The shape of the octahedral void is octahedral
The edge length of the crystal `A^+ B^-` is equal to the distance between `A^+` and `B^-` ions.

Solution :Octahedral void is so called because it is SURROUNDED by SIX atoms. Edge length of `A^+ B^-` crystal =2 x distance between `A^+` and `B^-`
Discussion
8.

Whatis usedin Rutherfordexperiment ?

Answer»

CATHODE RAYS
`He^(2+) ` rays
X-rays
`GAMMA`rays

Answer :B
Discussion
9.

Why are lithium salts commonly hydrated and those of the other alkali ions usually anhydrous?

Answer»

SOLUTION :`Li^(+)`IONS are the smallest of all alkali metal ions. Due to small size, they can polarise water molecules, attach them and get hydrated easily in comparison to other alkali metal ions. This is why lithium salts are COMMONLY hydrated, e.g. LICI `2H_2O`.
Discussion
10.

Which of the following is a false statement about boric acid, H_3 BO_3?

Answer»

It is a strong tribasic acid.
It does not act as proton donor but acts as a LEWIS acid by accepting hydroxyl ion.
It is PREPARED by acidifying an aqueous SOLUTION of boric acid.
It has a layer STRUCTURE in which planar `BO_3` units are joined by hydrogen bonds.

Solution :It is a strong tribasic acid.
Discussion
11.

The velocities of two particles A and B are 0.05 and 0.02ms^(-1) respectively. The mass of B is five times the mass of A. The ratio of their de- Broglie's wavelength is

Answer»

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

Solution :Given velocity of particle `A=0.05ms^(-1)`
velocity of PARTICLES `B=0.02 ms^(-1)`
Let the mass of particle A=X
:. The mass of particle `B=5x` de-Broglie's equation is `lambda=h/(mv)`
for particle A `lambda_(A)=h/(x xx0.5)`
for particle B `lambda_(B)=h/(5x xx0.02)`
E.q (i)//(ii) `lambda_(A)/lambda_(B)=(5x xx0.02)/(x xx0.05)`
`lambda_(A)/lambda_(B)=2/1`
or `2:1`
Discussion
12.

Which of the following biphenyl is optically active?

Answer»




Solution :This is a biphenylsystem in whichortho positions are OCCUPIED by groups and both the RINGS are not in ONE plane. THEREFORE, their mirror images are non-superimposable and the COMPOUND is optically active.
Discussion
13.

The resonance effect is defined as 'the polarity produced in the molecule by the interaction of two pi-bonds or between a pi-bond and lone pair of electrons present on an adjacentatom.' The effect is transmitted through the chain. In positive resonance effect, the transfer of electrons is away from an atom or substituent group attached to the conjugated system. This electron displacement makes certain positions in the molecule of high electron densities. In negative resonance effect, the transfer of electrons is towards the atom or substituent group attached to the conjugated system. The correct statement regarding a carbonyl compound with a hydrogen atom on its alpha carbon, is

Answer»

a CARBONYL COMPOUND with a hydrogen atom on its alpha-carbon RAPIDLY EQUILIBRATES with its corresponding enol and this process is KNOWN as carbonylation
a carbonyl compound with a hydrogen atom on its alpha-carbon rapidly equilibrates with its corresponding enol and this process is known as keto-enol tautomerism
a carbonyl compound with a hydrogen atom on its alpha-carbon never equilibrates with its corresponding enol
a carbonyl compound with a hydrogen atom on its alpha-carbon radidly equilibrates with its corresponding enol and this process is known as aldehyde-ketone equilibration.

Solution :is the correct answer.
Discussion
14.

The resonance effect is defined as 'the polarity produced in the molecule by the interaction of two pi-bonds or between a pi-bond and lone pair of electrons present on an adjacentatom.' The effect is transmitted through the chain. In positive resonance effect, the transfer of electrons is away from an atom or substituent group attached to the conjugated system. This electron displacement makes certain positions in the molecule of high electron densities. In negative resonance effect, the transfer of electrons is towards the atom or substituent group attached to the conjugated system. Which of the following carboxylate ions is the most stable ?

Answer»

`CH_(3)-overset(O)overset(||)(C)-O^(-)`
`Cl-CH_(2)-overset(O)overset(||)(C)-O^(-)`
`I-CH_(2)-overset(O)overset(||)(C)-O^(-)`

SOLUTION :STABILITY of carboxylate ion is related to the dispersal of negative CHARGE on the ion. It is maximum in carboxylate ion (d) since it has two electron withdrawing F atoms (-I -effect) attached to `ALPHA`-carbon atom.
Discussion
15.

Why are the following reactions not redox reactions ? BaCl_(2)(aq)+H_(2)SO_(4)(aq)toBaSO_(4)(s)+2HCl(aq)

Answer»

Solution :GIVEN REACTIONS do not INVOLVE any change in OXIDATION number.
Discussion
16.

The resonance effect is defined as 'the polarity produced in the molecule by the interaction of two pi-bonds or between a pi-bond and lone pair of electrons present on an adjacentatom.' The effect is transmitted through the chain. In positive resonance effect, the transfer of electrons is away from an atom or substituent group attached to the conjugated system. This electron displacement makes certain positions in the molecule of high electron densities. In negative resonance effect, the transfer of electrons is towards the atom or substituent group attached to the conjugated system. Which of the following shows +M effect ?

Answer»

`- N(CH_(3))_(2)`

`- CN`
Both (a) and (C)

SOLUTION :`-N (CH_(3))_(2)` shows `+ M` effect.
Discussion
17.

The resonance effect is defined as 'the polarity produced in the molecule by the interaction of two pi-bonds or between a pi-bond and lone pair of electrons present on an adjacentatom.' The effect is transmitted through the chain. In positive resonance effect, the transfer of electrons is away from an atom or substituent group attached to the conjugated system. This electron displacement makes certain positions in the molecule of high electron densities. In negative resonance effect, the transfer of electrons is towards the atom or substituent group attached to the conjugated system. Which of the following does not show resonance effect ?

Answer»

Buta-1, 3-diene
Acrylonitrile
Nitrobenzene
Isopropylisothiocyanate

Solution :
Discussion
18.

What is the coordination number of sodium in sodium oxide (Na_2O)?

Answer»

6
4
8
2

Answer :C
Discussion
19.

The value of K_c for the reaction 3O_(2)(g) is 2.0 xx 10^(-50) and 25^(@)C . If equilbrium concentration of O_(2) in 25^(@)C is 1.6 xx 10^(-2) . What is the concentration of O_(3) ?

Answer»

Solution :`3O_(2)(g) hArrr 2O_(3)(g)`
`K_(c) = ([O]^2)/([O_2]^3) or (2.0 XX 10^(-50)) = ([O_3]^2)/(1.6 xx 10^(-2))^3`
or`[O_3]^2 = (2.0 xx 10^(-50)) xx (1.6 10^(-2))^3`
`[O_3]^2 =(8.192 xx 10^(-56))^(1//2) = 2.86 xx 10^(-28) M`
Discussion
20.

What is energy gap in band theory ? Compare its size in conductors, semiconductors and insulators.

Answer»

Solution :Energy GAP in BAND theory means the gap of energy between VALENCE band and condcution band. The gap is in the order : Conductor lt SEMICONDUCTOR lt Insulator .
Discussion
21.

Which of the following statement about amorphous solids is incorrect ?

Answer»

They melt over a RANGE of TEMPERATURE
They are anisotropic
There is no orderly arrangement of particles
They are rigid and incompressible

Solution :Amorphous solids are isotropic , i.e., PHYSICAL properties LIKE electrical conductivity , refractive INDEX, thermal expansion etc. are identical in all directions.
Discussion
22.

What is the formula of brown ppt?

Answer»

`CR(OH)_(3)`
`Fe(OH)_(2)`
`FeCI_(3)`
`Fe(OH)_(3)`

Answer :D
Discussion
23.

The resonance effect is defined as 'the polarity produced in the molecule by the interaction of two pi-bonds or between a pi-bond and lone pair of electrons present on an adjacentatom.' The effect is transmitted through the chain. In positive resonance effect, the transfer of electrons is away from an atom or substituent group attached to the conjugated system. This electron displacement makes certain positions in the molecule of high electron densities. In negative resonance effect, the transfer of electrons is towards the atom or substituent group attached to the conjugated system. Which of the following free radicials is the most stable ?

Answer»




SOLUTION :It is the most STABLE because of HYPER CONJUGATION.
Discussion
24.

What is the difference between inductive effect and resonance effect?

Answer»

SOLUTION :Due to inductive effect only the electron density of bond INCREASES near to ONE atom and DECREASES near to other atom so bond become polar. In resonance effect the POSITION of electrons of `pi` bond change which is hypothetical. Such arrangement is not real.
Discussion
25.

The resonance effect is defined as 'the polarity produced in the molecule by the interaction of two pi-bonds or between a pi-bond and lone pair of electrons present on an adjacentatom.' The effect is transmitted through the chain. In positive resonance effect, the transfer of electrons is away from an atom or substituent group attached to the conjugated system. This electron displacement makes certain positions in the molecule of high electron densities. In negative resonance effect, the transfer of electrons is towards the atom or substituent group attached to the conjugated system. Which of the following intermediates is pyramidal in shape ?

Answer»

`H_(3) C^(o+)`
`H_(2) OVERSET(..)(C)`
`H_(3)C^(UNDERSET( : )(ɵ))`
`HC equiv C^(underset( : )(ɵ))`

Solution :`H_(3)overset(ɵ)(C):` is pyramidal in shape.
Discussion
26.

The resonance effect is defined as 'the polarity produced in the molecule by the interaction of two pi-bonds or between a pi-bond and lone pair of electrons present on an adjacentatom.' The effect is transmitted through the chain. In positive resonance effect, the transfer of electrons is away from an atom or substituent group attached to the conjugated system. This electron displacement makes certain positions in the molecule of high electron densities. In negative resonance effect, the transfer of electrons is towards the atom or substituent group attached to the conjugated system. What is the IUPAC name for :

Answer»

5-isobutyl-2-methylheptane
4-ethyl-2, 7-dimethylocatne
5- ehtyl-2, 7-dimethyloctane
2-methyl-5-(2-methylpropyl) heptane.

Solution :`{:(overset(1)(C)H_(3)-overset(2)(C)H-overset(3)(C)H_(2)-overset(4)(C)H-overset(5)(C)H_(2)-overset(6)(C)H_(2)-overset(7)(C)H-overset(8)(C)H_(3)),("|""|""|"),(""CH_(3)""CH_(2)""CH_(3)),("|"),(""CH_(3)):}`
4-ethyl-2, 7-dimethyloctane.
Discussion
27.

Which is the correct order of ionic radii given below?

Answer»

`Ca^(2+) gt K^(+) gt Cl^(-) gt S^(2-) gt P^(3-)`
`P^(3-) gt S^(2-) gt Cl^(-) gt Ca^(2+) gt K^(+)`
`K^(+) gt Ca^(2+) gt Cl^(-) gt S^(2-) gt P^(3-)`
`P^(3-) gt S^(2-) gt Cl^(-) gt K^(+) gt Ca^(2+)`

SOLUTION :`P^(3-) gt S^(2-) gt Cl^(-) gt K^(+) gt Ca^(2+)`

All have same (18) ELECTRONS, but nuclear charge INCREASE as a result order of IONIC radii decrease.
Discussion
28.

Which of the following alkenes will show geometrical isomerism ? (i) Propene,(ii) But-2-ene , (iii) But-1-ene , (iv) 2, 3-Dimethylbut-2-ene

Answer»

SOLUTION :(II) But-2-ene
Discussion
29.

Which of the following dissolves in water with a hissing sound?

Answer»

BLEACHING powder
marble
quick lime
slaked lime

Answer :C
Discussion
30.

Which of the following represents largest pressure ?

Answer»

1 atmosphere
1 bar
10 pounds per SQUARE INCH
1000 pascals or `N m^(-2)`

Solution :1 atm =101325 Pa or N `m^(-2)`
1 bar `=10^(5)` Pa or N `m^(-2)`=0.987 atm
14.7 1b/sq inch =1 atmospheric pressure at SEA LEVEL
Thus, 1 atm represents the largest pressure.
Discussion
31.

What is X in the following reaction ? MgCl_(2) +2H_92) O to X+ 2HCl +H_(2)O

Answer»

MgO
MG
`Mg(OH)_(2)`
`Mg(OH)Cl`

Solution :`MGCL _(2) +2H_(2)O to MgO+ 2HCl +H_(2)O`
Discussion
32.

Which of the following is an endothermic process?

Answer»

FIRST ELECTRON affinity of chlorine
SECOND electron affinity of oxygen
Formation of `NaCl` from gaseous ions
Hydration of `MgCl_2`

Answer :B
Discussion
33.

Write the formula of the compound of phosphorus which is obtained when conc. HNO_(3) oxidises?

Answer»

<P>

Solution :`{:(2HNO_(3)toH_(2)O+2NO_(2)+[O]xx10),(P_(4)+10[O]toP_(4)O_(10)),(P_(4)O_(10)+6H_(2)Oto4H_(3)PO_(4)):}/{:P_(4)+20HNO_(3)tounderset("Orthophosphoric ACID")(4H_(3)PO_(4))+20NO_(2)+4H_(2)O:}`
Discussion
34.

Which of the following is a primary pollutant

Answer»

`SO_(2)`
`NO_(2)`
PAN
`CO_(2)`

ANSWER :C
Discussion
35.

Which of the following is not a Lewis acid ?

Answer»

`AlCl_3`
`SnCl_4`
`FeCl_3`
`AlCl_(3) .6H_(2)O`

SOLUTION :`AlCl_(3) .6H_2O` is not a LEWIS ACID
Discussion
36.

Which of the following has the most acidic hydrogen?

Answer»




(a) and (b)

SOLUTION :Removal of `H^(+)` from compound .C. LEADS to AROMATIZATION
Discussion
37.

The stability and magnetic properties of a molecule can be well explained using the molecular orbital theory developed by F Hung and R.S.Mulliken.Draw the energy level diagram for the formation of the O_2 molecule.

Answer»

SOLUTION :REFER to TEXT
Discussion
38.

Define bond order according to the M.O.theory.

Answer»

Solution :Bond ORDER is DEFINED as ONE half of the difference between number of electrons in the bonding and the antibonding MOLECULAR orbitals.
Discussion
39.

Why a person surffering from high blood pressure is advised to take minimum quantity of common salt ?

Answer»

Solution :Osmotic PRESSURE is directly proportional to the concentration of solutes: Our body FLUID contains a number of solutes. On TAKING large amount of salt, IONS entering into the body fluid thereby raises the concentration of solutes. As a result, osmotic pressure INCREASES which may rupture the blood cells.
Discussion
40.

What happens to the PH of water when NH_(4)Cl solid is dissolved in it and why?

Answer»

Solution :PH Decrease: Because `NH_(4)CL` being salt of strong Acid and Weak base UNDERGOES Hydrolysis to give Acidic solution.
Discussion
41.

Whic of the following statements is incorrect ?

Answer»

`H_(2)O_(2)` has WEAK acidic property
`H_(2)O_(2)` has weak basic property
`H_(2)O_(2)` can ACT as OXIDISING agent
`H_(2)O_(2)` can act as a reducing agent

Answer :B
Discussion
42.

Which of the following is correct formula of ethyl acetate?

Answer»

`CH_(3)- UNDERSET(underset(O)(||))(C )-O - CH_(2)-CH_(3)`
`CH_(3) - underset(underset(O)(||))(C )-underset(underset(O)(||))(O)-CH_(2)-CH_(3)`
`CH_(3)-CH_(2)-O-CH_(2)- underset(underset(O)(||))(C )-OH`
`CH_(3)-CH_(2)-COO-CH_(3)`

ANSWER :A
Discussion
43.

When does the transport of oxygen to different body cells stop ?

Answer»

SOLUTION :(i) Carbon monxide ( CO ) combines with haemoglobin ( HB) of the RBCs about 300times more readily than oxygen to form carboxy haemoglobin COMPLEX.
`Hb + CO hArr HbCo`
(ii) THUS, Hb will not be able to combine with oxygen to for oxyghaemoglobin complex.
(iii) Hence the transport of oxygento different BODY cells does not occur ( stops ) .
Discussion
44.

Which compound is used to remove the temporary hardness of water in Clark.s method.

Answer»

Solution :In clark.s METHOD, the lime water `(Ca(OH)_2)` is USED to REMOVE the TEMPORARY hardness.
Discussion
45.

Underlined carbon is sp hybridised in-

Answer»

`CH_(3)CH=CH_(2)`
`CH_(3)CH_(2)-NH_(2)`
`CH_(3)CONH_(2)`
`CH_(3)CH_(2)CN`

Answer :D
Discussion
46.

Which elements isexpected tohave lowestfirstionizationenthalpy ?

Answer»

SR
As
Xe
S

SOLUTION :S' LIES in the3rd 'As' in 4thwhile 'Sr' and 'Xe'lie in thefifthperiod. Exceptnoblegasesin generalionizationenthalpyof the elements decreasesas theserialnumberof the periodincreases. Thusionizationenthalpiesof SandAs are HIGHERTHAN thatof Sr.ButXebeingthe noblegas has thehighestionizationenthalpy . ThusSr hasthe lowestionizationenthalpy .
Discussion
47.

What is the action of alkali metals with oxygen (air) ?

Answer»

Solution :Alkali metals react with oxygen to FORM their oxides.
EX. Lithium forms monoxide
`4 Li + O_(2) overset(Delta)(to) 2Li_(2) O` (Lithium monoxide)
SODIUM forms peroxide
`2Na + O_(2) to Na_(2) O_(2)` (sodium peroxide)
Others metals form super oxides as
`M + O_(2) to MO_(2)` [Where M = K, Rb, Cs)
Discussion
48.

The volume of 0.0168 mol of O_(2) obtained by decomposition of KClO_(3) and collected by displacement of water is 428 ml at a pressure of 754 mm Hg at 25^(@)C. The pressure of water vapour at 25^(@)C is

Answer»

18 mm HG
20 mm Hg
22 mm Hg
245 mm Hg.

Solution :Pressure of dry gas, P=nRT/V
`=0.0168xx(0.0821xx1000xx760" ML "mm)xx(298)/(428)`
730 mm
Pressure of moist gas=754 mm. Hence, pressure of water vapour =(754-730)mm=24 mm.
Alternatively, volume of `0.0168" mol"` of `O_(2)` at STP
`=0.0168xx22400=376.3" ml"`
THUS, `V_(1)=376.3" ml", P_(1)=760" mm", T_(1)=273" K"`
`V_(2)=428" ml",P_(2)=?,T_(2)=298" K"`.
Calculate `P_(2)`.
Discussion
49.

Which of the following mixtures can be seperated into its costituents by using concentrated sodium hydroxide ?

Answer»

`AI^(3+)` and `FE^(3+)`
`AI^(3+)` and `An^(2+)`
`ZN^(2+)`and `PB^(2+)`
`Sn^(2+)` and `Pb^(2+)`

Solution :`AI^(3+)` dissolvesin conc NAOH but `Fe^(3+)` does not
`Fe^(3+)+NaOHrarrFe(OH)_(3)`
Discussion
50.

Which of the following statement is true?

Answer»

Allyl CATION is more STABLE than cyclo tri phenyl cation
Cyclopropenyl cation is less stable than the allylcation
Cyclopropenyl cation more stable than allyl cation
Cyclopropenyl cation and allycation are equally stable

Solution :Cyclopropenyl cation is more stable then the allyl cation because the stuctures FITS the HuCKel ( 4n +2) rule for N = 0
Discussion