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.

In the preparation of dextron one of the raw material is lactic acid another is

Answer»

GLYCOLIC ACID
valeric acid
PHTHALIC acid
OXALIC acid

ANSWER :A
Discussion
2.

In the preparation of compounds of Xe, Bartlett had taken O_(2)^(+) PtF_(6)^(-) is a base compound. This is because ............

Answer»

Both `O_(2)`and XE have same size.
Both `O_(2)`and Xe have same ELECTRON gain enthalpy.
Both `O_(2)`and Xe have almost same IONISATION enthalpy.
Both Xe and `O_(2)`are gases.

Answer :C
Discussion
3.

In the preparation of chlorobenzene from aniline, the most suitable reagent is

Answer»

Chlorine in the PRESENCE of ultraviolet light
Chlorine in the presence of `AlCl_(3)`
NITROUS acid followed by heating with `Cu_(2)Cl_(2)`
`HCl and Cu_(2)Cl_(3)`

SOLUTION :
Discussion
4.

In the preparation of compounds of Xe, Bartlett had taken O_(2)^(+) PtF_(6)^(-) as a base compound. This is because

Answer»

both `O_(2)` and Xe have same SIZE
both `O_(2)` and Xe have same ELECTRON gain ENTHALPY
both `O_(2)` and Xe have ALMOST same ionsiation enthalpy
both Xe and `O_(2)` are gases

Answer :C
Discussion
5.

In the preparation of compounds of Xe, Bartlett had taken O_(2)^(+) Pt F_(6)^(-)as a base compound. This is because

Answer»

both `O_2` and Xe have same size
both `O_2` and Xe have same ELECTRON GAIN ENTHALPY.
both `O_2` and Xe have almost same ionization enthalpy.
both Xe and `O_2` are gases.

ANSWER :C
Discussion
6.

In the preparation of compounds of Xe, Bartlett had taken O_(2)^(+)PtF_(6)^(-) as a base compound. This is because

Answer»

both `O_2` and XE have same size
both `O_2` and Xe have same electron GAIN enthalpy.
both `O_2` and Xe have almost same ionization enthalpy.
both Xe and `O_2` are gases.

ANSWER :C
Discussion
7.

In the preparation of bakelite polymer by using base catalyst , the intermediate species formed from phenol and formaldehyde is

Answer»




ANSWER :A
Discussion
8.

In the preparation of aromatic ether one of the reactant is sodium phenoxide, another ts

Answer»

R-OH
R-Cl
R-CHO
R-COONa

Answer :B
Discussion
9.

In the preparation of chlorine from HCI,MnO_2 act as :

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REDUCING agent
Oxidising agent
Catalytic agent
Dehydrating agent

Answer :B
Discussion
10.

In the preparation of amines by Gabriel phthalimide synthesis the second product that is obtained is

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phthalimide
phthalic acid
phthaloyl chloride.
disodium phthalate.

Answer :D
Discussion
11.

In the preparation of amorphous silicon, HF acid is used to remove

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Mg
`SiO_(2)`
`Si `
none of these

SOLUTION :AMORPHOUS silicon is PREPARED by the reduction of silica (rocks). EXTRA pure silicon is obtained by the removal of `SiO_(2)` by HF. `SiO_(2) +4HF to SiF_(4) +2H_(2)O`
Discussion
12.

In the preparation of an ester the commonly used dehydrating agent is :

Answer»

Phosphorus pentoxide
Anhydrous CALCIUM chloride
Anhydrous aluminium chloride
CONCENTRATED SULPHURIC acid

Answer :D
Discussion
13.

In the preparation of an ester , the commonly used dehydrating agent is :

Answer»

PHOSPHORUS pentoxide
Anhydrous ALUMINIUM achloride
Anhydrous CALCIUM chloride
Conc . Sulohuric ACID .

ANSWER :D
Discussion
14.

In the preparation of alkyl halide from alkene and halogen which of the following reaction is involved

Answer»

FREE radical substitution
NUCLEPHILIC ADDITION
ELECTROPHILIE substitution
nucleophilicsubstitution

SOLUTION :free radical substitution
Discussion
15.

In the preparation of alkanes from hydrogenation ofalkenes and alkynes. Finely divided catalysts are used which of the following statement(s) is/are correct regarding these catalysts (i) Platinum and palladium catalyse the reaction at room temperature. (ii) Nickel catalyse the reaction at relatively higher temperature and pressure. (iii)Platinum and palladium catalyse the reaction at higher temperature.

Answer»

I and iii
I and ii
ii and iii
I only

Solution :Dihydrogen gas ADDS to alkenes and ALKYNES in the presence of finely divided catalysts like platinum, palladium or nickel to form alkanes. These metals ADSORB dihydrogen gas on their surfaces and ACTIVATE the hydrogen-hydrogen bond. Platinum and palladium catalyse the reaction at room temperature but relatively higher temperature and PRESSURE are required with nickel catalyst.
Discussion
16.

In the preparation of acetic acid from acetaldehyde the catalyst used in ……

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SOLUTION :Rh/Ir COMPLEX
Discussion
17.

In the preparation of alkanes, a concentrated aqueous solution of sodium or potassium salts of saturated carboxylic acid are subjected to

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HYDROLYSIS
Oxidation
Hydrogenation
ELECTROLYSIS

Solution :`2CH_3COONa+2H_2Ooverset"electrolysis"to CH_3-CH_3+2CO_2+2NaOH+H_2`
Discussion
18.

In the preparaiton of O_2 from KClO_3, MnO_2 acts as

Answer»

Activator
Catalyst
OXIDIZING agent
Dehydrating agent

Answer :B
Discussion
19.

In the precipitation of the iron group in qualitative analysis, amonium chloride is added before adding ammonium hydroxide to

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DECREASE concentration of `OH^(-)` ions
Prevent interference by phosphate ions
Increase concentration of `CL^(-)` ions
Increase concentration of `NH_(4)^(+)` ions

Solution :As `NH_(4)Cl` is a strong ELECTROLYTE. It suppresses the ionization of `NH_(4)OH`, so the concentration of `OH^(-)` ions in the solution is decreased, but it is sufficient to precipitate the III group basic radicals because the solubility product of III group hydroxides is lower than IV,
V and VI group hydroxides as
Discussion
20.

In the precipitation of soap, which can be used insteadof NaCl

Answer»

`NA`
`CH_(3)COONa`
`Na_(2)SO_(4)`
SODIUM silicate

Answer :C
Discussion
21.

In the precipitation of iron group in qualitative analysis, NH_4Cl is added before the addition of NH_4OH:

Answer»

To prevent the interference of phosphate
To decrease `NH_4^+` IONS concentration
To increase `OH^-` ions concentration
To prevent the precipitation of SUBSEQUENT groups

Answer :D
Discussion
22.

In the precipitation of group III in qualitative analysis ammonium chloride is added before adding NH_4OH to :

Answer»

decrease the concentration of `OH^(-)`
increase concentration of `CL^(-)`
PREVENT interference of `PO_4^(3-)`
increase the concentration of `NH_4^(+)` .

ANSWER :A
Discussion
23.

In the precipitate of the iron groupin qualitativev anlysis ammonium chloride is added before adding ammonium hydroxide to

Answer»

Decreases CONCENTRATION of `OH^(Θ)` ions
Prevent INTERFERENCE by phosphate ions
increases concentration of `CI^(Θ)` ions
Increases concentration of `NH_(4)^(o+)` ions

Solution :Only FE ,Cr and AIare PRECIPITATE as their hydroxide
Discussion
24.

In the potential energy curve for the formation of H_2molecule as a function of internuclear distance of H atoms, what happens at the minimum in the curve?

Answer»

net FORCE of attraction EQUALS to of force repulsion
most STABLE state of `H_2` is achieved
system aquires minimum energy
All of these

Answer :D
Discussion
25.

In the plot of molar conductivity (^ m) vs square root of concentration (c^(1//2)) following curves are obtained for two electrolytes A and B : Answer the following: (i) Predict the nature of electrolytes A and B. (ii) What happens on extrapolation of ^ m to concentration approaching zero for electrolytes A and B?

Answer»

SOLUTION :(i) A strong electrolyte, B-Weak electrolyte
(ii) ^° m for weak ELECTROLYTES cannot be OBTAINED by EXTRAPOLATION while ^° m for strong electrolytes can be obtained as INTERCEPT.
Discussion
26.

In the polymerization of acrylonitrile, most commonly used initiator is

Answer»

A CATION
An anion
A FREE radical
ZWITTER ion

Answer :B
Discussion
27.

In the plot of concentration of reactant versus time, the tangent at any instant of time has a ……………. Slope (positive or negative or zero).

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ANSWER :NEGATIVE
Discussion
28.

In the Pidgeon process, Mg is produced by:

Answer»

electrolysis of fused `MgCI_(2)`
reducing calcined dolomite with ferrosilicon at high TEMPERATURE under pressure
both are CORRECT
NONE is correct

Solution :Pidgeon PROCESS in pyro-extraction
Discussion
29.

In the periodic table, the highest ionisation enthalpies are for:

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Halogen
alkaline EARTH metals
Alkali metals
Chalcogens.

Answer :B
Discussion
30.

In the periodic table, metallic chracter of the elements shows one of the following trend:

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Decreases DOWNN the GROUP and increases across the period
Increases down the group and decreases across the period
Increases across the period and also down the group
Decreases across the period and also down the group

Answer :B
Discussion
31.

In the periodic table metals usually used as catalysts belong to

Answer»

f-block
d-block
p-block
s-block

Solution :d-Block METAL USUALLY USED as CATALYST.
Discussion
32.

In the periodic table in going down in fluorine group:

Answer»

IONIC RADIUS increases
Electronegativity increases
Ionization POTENTIAL increases
Reactivity increases

Answer :A
Discussion
33.

In the periodic table going down in fluorine group:

Answer»

IONIC RADIUS increases
Eelctronegativity increases
reactivity increases
Ionisation POTENTIAL increases.

Answer :D
Discussion
34.

In the pair, (CH_(3))_(3)C Cl and CH_(3)Cl, CH_(3)Cl will react faster in S_(N)2 reaction with OH^(-). Explain.

Answer»

Solution :In `S_(N)2` reactions, reactivity depends upon the steric hindrance. In `(CH_(3))_(3)C CL`, the `ALPHA`-carbon carrying the Cl atom is attached to three `CH_(3)` groups but in `CH_(3)-Cl`, the carbon carrying the Cl atom is attached to three hydrogen atoms. since `CH_(3)` group is MUCH bigger than H-atoms, therefore, `(CH_(3))_(3)C Cl` suffers GREATER steric hindrance to nucleophilic attack by `OH^(-)` than `CH_(3)Cl` and hence `CH_(3)Cl` will react faster than `(CH_(3))_(3)C Cl` in `S_(N)2` reaction with `OH^(-)`.
`underset("Methyl chloride (carbon carrying Cl atom is attached to three small H-atoms, no steric hindrance, more reactive)")(CH_(3)-Cl)""underset("tert-Butyl chloridee (Carbon carrying Cl atom is attached to three bigger "CH_(3)" groups, more steric hindrance, less reactive)")((CH_(3))_(3)C-Cl)`
Discussion
35.

In the oxyacids of phosphorous the hybridisation of phosphorous is

Answer»

`SP^3`
`sp^2`
sp
`dsp^2`

ANSWER :A
Discussion
36.

In the oxyacids of chlorine Cl-O bond contains:

Answer»

`dpi-dpi` BONDING
`ppi-dpi` bonding
`ppi-ppi` bonding
None

Answer :B
Discussion
37.

In the oxidation of Cu, then reaction which taken place in bessemer converter is

Answer»

`2CuFeS_(2)+O_(2)rarr Cu_(2)S+FeS+SO_(2)`
`2Cu_(2)S+3O_(2)rarr 2Cu_(2)O+2SO_(2)`
`2Cu_(2)O+Cu_(2)Srarr 6Cu+SO_(2)`
`2FeS+3O_(2)rarr 2FeO+2SO_(2)`

Answer :C
Discussion
38.

In the oxidation of N_(2)H_(4) "to"N_2equivalent weight of N_(2)H_(4)would be........

Answer»


Solution :`overset(2xx2)(N_(2)H_4)rarroverset(2xx2)(N_(2))+4E^(-)`
EQUIVALENT weight = `{:(""GMW),(bar"change in oxidation "),("state for one"),("formula unit"):}=cancel(32)/cancel(4)=8, :. "EQ. wt of "N_(2)H_(4)=8``
Discussion
39.

In the oxidation of ferric oxalate [Fe_2(C_2O_4)_3] to carbondioxide, if 18F of electricity is required how many moles of ferric oxalate is oxidized

Answer»


Solution :`[(Fe_2)(C_2O_4)_3] overset(6F)to 6CO_2`
` +3 "" +4`
`6F to 1 " mole " , 18 F to N = ? , n = 18//6 = 3 ` moles
Discussion
40.

In the octahedral crystal field, there is splitting of d orbitals. Which of the following d orbitals constitute the higher energy e_(g) set of orbitals.

Answer»

`d_(xy), d_(xy)`
`d_(z^(2)), d_(yz)`
`d_(xy), d_(x^(2_(-)y^(2))`
`d_(x^(2_(-)y^(2))), d_(z^(2))`

Solution :Lets us assume the six ligands are positioned symmertically along the Cartesian axes, with the central metal atom/ion at the origin. In an octahedral coordination entity with six ligands SURROUNDING the metal atom/ion, there will be repulsion between the electron inmetal d orbitals and the electrons (or negative charges) of the ligands. As the ligands approach form infinity toward the central metal atom/ion, first there is an increase in the energy of d orbitals relative to that of the free ion just as would be the CASE in a spherical field. As the distance of complex FORMATION approaches, such a repulsion is more when the metal d orbital is directed towards the LIGAND than when it is away form the ligand. Thus, the `d_(x^(2)-y^(2))` and `d_(z^(2))` orbitals lying along the axes and pointing towards the approaching ligands GET repelled more strongly than `d_(xy)` , `d_(yz)` , `d_(xz)` orbitals which have lobes directed between the axes and pointing a way form the approaching ligands. Consequently, the `d_(x^(2)-y^(2))` and `d_(z^(2))` orbitals get raised in energy while `d_(xy)` `d_(yz)` and `d_(xz)` orbitals are lowered in energy relative to the avarege energy in the spherical crystal field.
Discussion
41.

In the octahedral complexes, if the (n-1)d orbitals are involved in hybridisation, they are called..............and..........complexes.

Answer»


ANSWER :The LINEAR ORBITAL complexes, low spin complexes (or) Spin PAIRED complexes.
Discussion
42.

In the nucleotide namely adenosine-5'-tri phosphate, the sequence of linkages among N(base), C(sugar) and P(phosphate) is

Answer»

`C-P-N-P-P`
`N-C-P-P-P`
`P-C-N-P-P`
`P-P-P-C-N`

ANSWER :A
Discussion
43.

In the nuclear transmutation. ""_(4)^(9)Be + X to ""_(4)^(8)Be + Y (X, Y) is (are)

Answer»

<P>`(GAMMA, n)`
`(p , D)`
`(n, D)`
`(gamma, p)`

Solution :`""_(4)^(9)Be + UNDERSET((X))(""_(0)^(0)gamma) to ""_(4)^(8)Be + underset((Y))(""_(0)^(1)n)`
`""_(4)^(9)Be + underset((X))(""_(1)^(1)p) to ""_(4)^(8)Be + underset((Y))(""_(1)^(2)D)`
Discussion
44.

In the nuclear transmutation : ._(4)^(9) Be + X rarr _(4) ^(8) Be +Y (X,Y) is (are)

Answer»

`(gamma, n)`
`(p, D)`
(n, D)
`(gamma, p)`

Solution :`""_(4)^(9)Be + ""_(B)^(a)X rarr ""_(4)^(8)Be + ""_(d)^(c )Y`
`4+b=4+d` gamma`- ""_(0)^(0)gamma`
`9+a=8+C`, deutorium `-""_(1)^(2)D`
proton `-""_(1)^(1)p`
Discussion
45.

In the nuclear reaction ._(92)U^(238) rarr ._(82)Pb^(206), the number of alpha and beta particles decayed are

Answer»

`4 alpha, 3 beta`
`8 alpha, 6 beta`
`6 alpha, 4 beta`
`7 alpha, 5 beta`

SOLUTION :NUMBER of `alpha`- particles `= (238 - 206)/(4) = 8`
Number of `beta`- particles `= 2XX 8 - 92 + 82 = 6`
Discussion
46.

In the nuclear reactions the speed of the neutrons is slowed down by

Answer»

HEAVY WATER
Ordinary water
Zinc rods
Molten CAUSTIC soda

Solution :Heavy water is `D_(2)O`
Discussion
47.

In the nuclear transmutation ._(4)^(9)Be + X rarr ._(4)^(8)Be + Y (X, Y) is (are)

Answer»

<P>`(GAMMA, N)`
`(p, D)`
`(n, D)`
`(gamma, p)`

Solution :`._(4)Be^(9) + X rarr ._(4)Be^(8) + Y`
If X is `._(0)gamma^(0)` then Y is `._(0)n^(1)`
If X is `._(1)p^(1)` then Y is `._(1)D^(2)`
Discussion
48.

In the nuclear reaction , ""_(92)^(235)U to _(82)^(207)Pb, the number of alpha and beta- particles lost would be

Answer»

`8,4`
`6,2`
`7,4`
`4,3`

Solution :`""_(92)^(235)U to _(82)^(207)Pb+x_(2)^(4)alpha+y_(-1)^(0)beta`
`235=207+4ximpliesx=7`
`92=82+2x-y` or `y=4`
Discussion
49.

In the nuclear reaction : ""_(84)^(215)Po""overset(-alpha)toPboverset(-alpha)toBioverset(-beta)toPo, the mass number of product is :

Answer»

84
207
215
213

Answer :B
Discussion
50.

In the nuclear fission ._(1)H^(2) + ._(1)H^(2) rarr ._(2)He^(4) the masses of ._(1)H^(2) and ._(2)he^(4) are 2.014 mu and 4.003 mu respectively. The energy released/atom of helium formed is ....MeV

Answer»

16.76
26.38
13.26
23.275

Solution :`Delta m = (2 XX 2.014 - 4.003) m u = 0.023"mu"`
1 amu `~~ 936 MeV`
`E = 0.025 xx 936`
E per nucleon `= (93.6)/(4) = 23.4MeV`
Discussion