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.

From gold amalgam , gold may be recovered by :

Answer»

Addition of Zn metal
ELECTROLYTIC refining
DISTILLATION
DISSOLVING Hg in `HNO_3`

ANSWER :C
Discussion
2.

From Gabrielphtalimide sythesis aromaticprimary aminecannotbeprepared .

Answer»

Ar - X do nitundergoesnucleophilicsubstituionreaction
Ar-Xis stabledue toresonatingstructures
Ar-X is highlyreactive dueto C - X BONDIS veryweak
Ar-Xis notstable

ANSWER :A
Discussion
3.

From Elligham diagram the correct statements (a) 4cu+O_(2) rarr 2Cu_(2)O (b)2C+O_(2) rarr2CO ( c)2Zn+O_(2) rarr 2ZnO

Answer»

At temeperature above `t_(1)^(0)C` "Carbon" can reduce `Cu_(2)O`
At temeperature above `t_(3)^(0)C` "Carbon" can reduce `ZNO`
Reduction of `Cu_(2)O` with carbon REQUIRES HIGH temperature when COMPARED with the reduction of ZnO by carbon
All

Answer :1
Discussion
4.

From fluorine to iodine, the electronegativity,

Answer»

DECREASES
increases
first decreases then increases
changes randomly.

Answer :D
Discussion
5.

From each of the following pairs of compounds, selects the one-which give positive iodoform test (a) Sec-butyl alcohol and Tert-butyl alcohol (b) Formaldehyde and Acetaldehyde ( c) Acetaone and Methyl alcohol

Answer»


SOLUTION :(a) Sec-butyl alcohol, (b) Acetaldehyde, (C ) ACETONE
Discussion
6.

From Ce to Lu atomic size decreases

Answer»

18 PM
`8 Pm`
`12 Pm`
`10 Pm`

ANSWER :D
Discussion
7.

From Bragg's equation which one of the following is wrong?

Answer»

INCIDENT ANGLE `(theta)` value is in between `0^(@)` to `90^(@)`
`2d lt N lambda`
order of diffraction 'n' is an integer
as `lambda` of x-rays increases, incident angle for first order diffraction increases 

Answer :B
Discussion
8.

From B_2H_6 all the following can be prepared except :

Answer»

`H_3BO_3`
`B_2O_3`
`B_2(CH_3)_6`
`NaBH_4`

ANSWER :D
Discussion
9.

From analysis and molecular weight determination the molecular formula of a compound (A) is C_(3)H_(7)NO. The compound gives the following information. i) On hydrolysis it gives an amine (B) and Carboxylic acid (C) ii) Amine (B) reacts with benzne sulphonyl chloride and gives a product which is insoluble in aqouesous sodium hydroxide solution iii) Acid (C) on reaction with Tollens reagent gives a silver mirror. Compound 'A' is

Answer»

`CH_(3)-OVERSET(O)overset(||)C-NH-CH_(3)`
`H-overset(O)overset(||)C-N(CH_(3))_(2)`
`CH_(3)CH_(2)-overset(O)overset(||)C-NH_(2)`
`H_(2)N-CH_(2)CH_(2)-CHO`

SOLUTION :DMF
Discussion
10.

From argentite (Ag_2S) ore the method used for obtaining metallic silver is:

Answer»

Fused MIXTURE of `Ag_2S` and `KCI` is electrolysed
`Ag_2S` is reduced with `CO`
`Ag_2S` is ROASTED to `Ag_2O` which is reduced with carbon
Treating argentite with `NaCN` SOLUTION followed by METAL displacement with zinc

Answer :D
Discussion
11.

From aqueous solution of ZnSO_(4), normal zinc carbonate may be precipitated by

Answer»

Boiling with `CaCO_(3)`
Adding `Na_(2)CO_(3)`
Adding `NaHCO_(3)`
Passing `CO_(2)`

SOLUTION :`ZnSO_(4)+2NaHCO_(3)rarr ZnCO_(3)+Na_(2)SO_(4)+H_(2)O+CO_(2)`
Discussion
12.

From analysis and molecular weight determination the molecular formula of a compound (A) is C_(3)H_(7)NO. The compound gives the following information. i) On hydrolysis it gives an amine (B) and Carboxylic acid (C) ii) Amine (B) reacts with benzne sulphonyl chloride and gives a product which is insoluble in aqouesous sodium hydroxide solution iii) Acid (C) on reaction with Tollens reagent gives a silver mirror. What is compound (B) ?

Answer»

`CH_(3)NH_(2)`
`NH_(3)`
`NH(CH_(3))_(2)`
`CH_(3)CH_(2)-NH_(2)`

SOLUTION :`2^(@)` amine
Discussion
13.

From analysis and molecular weight determination the molecular formula of a compound (A) is C_(3)H_(7)NO. The compound gives the following information. i) On hydrolysis it gives an amine (B) and Carboxylic acid (C) ii) Amine (B) reacts with benzne sulphonyl chloride and gives a product which is insoluble in aqouesous sodium hydroxide solution iii) Acid (C) on reaction with Tollens reagent gives a silver mirror. Compound 'C' is

Answer»

`CH_(3)-OVERSET(O)overset(||)C-OH`
`CH_(3)CH_(2)-overset(O)overset(||)C-OH`
`H-overset(O)overset(||)C-OH`
None

Solution :Formic acid
Discussion
14.

From an isolated system, DeltaU=0, what will be DeltaS?

Answer»

0
`GT0`
`lt0`
`ge0`

SOLUTION :For an isolated system, `DeltaU=0` and for a spontaneous process, total entropy change must be positive.
`DeltaS gt 0`.
Discussion
15.

From an aqueous solution of zinc sulphate , normal zinc carbonate may be precipitated by :

Answer»

PASSING `CO_2`
WARMING with `NaHCO_3`
Adding `Na_2CO_3`
BOILING with `CaCO_3`

Answer :B
Discussion
16.

From amongst the following electronic configuration, find out the alkaline earth element.[Ar]4s^2 [Ar]3d^5 4s^2 [Ar]3d^10 4s^2

Answer»

[AR] `4s^2`,
[Ar] `3d^54s^2`
[Ar]`3d^10 4s^2`

ANSWER :A
Discussion
17.

From amongst the following alcohols, the one that would react fastest with conc.HCl and anhydrous ZnCl is

Answer»

1-Butanol
2-Butanol
2-Methylpropan-2-ol
2-Methylpropanol-1

Answer :C
Discussion
18.

From amongst the following alcohols, the one that would react fastest with conc. HCl and anhydrous ZnCl_(2), is

Answer»

2-methylpropanol
1-butanol
2-butanol
2-methylpropan-2-ol.

Solution :Lucas reagent, i.e., conc. `HCL`+ANHYD. `ZnCl_(2)` reacts FASTEST with `3^(@)` ALCOHOLS. Thus, option (d), i.e., 2-methylpropan-2-ol is correct.
Discussion
19.

From amongst the following alcohols, the one that would react fastest with conc. HCl and anhydrous ZnCl_2 is

Answer»

I- BUTANOL
2- Butanol
2-Methylpropan -2-ol
2- Methylpropanol -1

ANSWER :C
Discussion
20.

From among the following elements choose one p-block element:

Answer»

NA
Be
Ca
Al

Answer :D
Discussion
21.

From a study of properties of neighbouring elements, the properties of an unknown element can be predicted - justify with an example.

Answer»

Solution :Mendeleev left some gaps in the PERIODIC table. He predicted the properties of these unknown elements after studying the properties of the neighbouring elements. When he proposed the periodic table. The elements scandium (Z = 21) , gallium (Z = 31) and germanium (Z = 32) were unknown. Not only he predicted their properties but also NAMED them eka-boron, eka-aluminium and eka-silicon respectively. The three elements were soon discovered within 20 years of his pronouncement of the 'periodic law' (during his life time). It is astonishing to SEE that when the properties of these elements were studied, these showed a remakable agreement with those predicted by Mendeleev.
In addition to the above three elements, Mendeleev the discovery of some more elements:
Examples:
`{:(S.NO.,"properties of Eka-silicon predicted by Mendeleev(1871)","Properties of Germanium discoverved by Winkler(1886)"),(1.,"Atomic weight"72,"Atomic weight"72.6),(2.,"SPECIFIC gravity"5.5,"Sp.gravity"5.46),(3.,"Colour-dirty grey","Colour-greyish white"),(4.,"Specific heat 0.073","Specific heat 0.076"),(5.,"Oxide"-EsO_(2)"less basic than"SnO_(2)",but more basic than"Si_(2)OSp.gr.4.70",refractory","Oxide"-GeO_(2)",slightly basic SP.gr."4.70", refractory"),(6.,"Chloride"-EsCl_(4) a "liquid, B.P. below"100^(@)C,"Chloide"-GeCl_(4)",liquid B.P."86.5^(@)C):}`.
Discussion
22.

From acrylic acid prepare gamma-amino butyric acid. beta-aminopropionic acid (beta-alanine).

Answer»

SOLUTION :The `-NH_(2)` and the additional C are introduced from `CN^(-)` which REACTS with the ACID by Michael type addition.
Discussion
23.

From among following pairs, number of pairs in which first compound is more basic than second compound is

Answer»


SOLUTION :Resonance `UARR` b.c `DARR`, `2^(@)` amines are more basic than `3^(@)R-NH_(2)`
Discussion
24.

From a mixture of yellow P and red P, yellow P can be removed by

Answer»

heating with CONC. `H_(2)SO_(4)`
heating with conc. `HNO_(3)`
heating with NAOH (aq)
NONE of these

Solution :Only yellow P reacts with NaOH(aq)
`P_(4)+3NaOH+3H_(2)O to 3NaH_(2)PO_(2)+PH_(3)`
Discussion
25.

From a solution of CuSO_4 , the metal used to recover copper is :

Answer»

Na
Ag
Hg
Fe

Answer :D
Discussion
26.

From a porous vessel containing equimolar proportions of hydrogen and oxygen, the composition by mass of the mixture effusing out is : hydrogen and oxygen in the ration of

Answer»

`1:4`
`2 SQRT( 2) : 1 `
`1: 2 sqrt(2)`
`4:1`

Solution :`( "Rate of effusion of " H_(2))/( "Rate of effusion "O_(2)) = ( " Mass" ( H_(2))//t) /( "Mass" ( O_(2))//t) = sqrt((32)/( 2))`
`("Mass of " H_(2))/( "Mass of " O_(2)) = ( 4)/(1)`
or `4:1`
Discussion
27.

From a mixture of amino acids the constituents can be separated by

Answer»

ion-exchange chromatography
electro-osmosis
electrophoresis
Both (1) and (3)

Solution :Electrophoresis can be used to separate and identify amino acids: If a filter paper-strip moistenedwith a solution of a mixture of `A A's` is placed between two electrodes, the charged MOLECULE will migrate to one electrode or the other at a RATE that depends on its net charge and the applied voltage. The net charge depend on the pH. The strip is then STAINED with a reagent that reacts with the `A A`, there by forming a colour whose position on the strip is COMPARED for identification with that of a known sample.
A mixture of `A A's` can also be separated by ion-exchange chromatoography: the column is charged with an ion-exchange resin with charged groups at tis surface. A cation - exchange resin, i.e., `R - SO_(3)^(-) NA^(+) (R=` resin), exchanges it cation`(Na^(+))` for positively charged `A A's` in acid when most `A A's` are cations. Separation depends on the rate of movement of the positively charged `A A's` down the column as the exchange occurs. The rate of movement is inversely proportional to the magnitude to the + charge on the `A A`.
Discussion
28.

From 200mg of CO_(2),10^(21) molecuels are removed. How many moles of CO_(2) are left?

Answer»

Solution :Gram-molecular mass of `CO_(2)=44g`
Mass of `10^(21)` molecuels of `CO_(2)=(44)/(6.02xx10^(23))xx10^(21)=0.073g`
Mass of `CO_(2)` left `=(0.2-0.073)=0.127g`
NUMBER of MOLES of `CO_(2)` left `=(0.127)/(44)=2.88xx10^(-3)`
Discussion
29.

From +6 to +1 oxidation state is shon by the element of …… group

Answer»

V-B
VI-B
VII-B
VIII

Solution :MAXIMUM no. or `E^(-)` in LAST SHELL =6.
Discussion
30.

From 200 mg of CO_(2),10^(21) molecules are removed. How many moles of CO_(2) are left ?

Answer»

Solution :Total no. Of MOLES of `CO_(2) = ("wt.in g")/("mol. Wt")`
`=0.2/44 =0.00454`
No. Of moles REMOVED `=(10^(21))/(6.022 xx 10^(23)) = 0.00166`
No. Of moles of `CO_(2)` LEFT `=0.00454 - 0.00166=0.00288`
Discussion
31.

Friedel-Craft's reaction using MeCl and anhydrous AlCl_3 will take place most efficiently with

Answer»

Benzene
Nitrobenzene
Acetophenone
Toluene

Solution :In Friedel-Craft's reaction, an electrophile ATTACKS on benzene ring. Thus, higher the electron density on benzene ring , more readily the reaction will takes place. Thus PRESENCE of electron donating group will increase the reactivity and presence of electron ATTRACTING group will decrease the reactivity TOWARDS Friedel-Craft's reaction. Thus the most reactive is toluence.
Discussion
32.

Friedel Creft acetylation of benzene gives

Answer»

benzophenone
acetophenone
ALKYL benzene
diphenyl

ANSWER :B
Discussion
33.

Frinkelestein reaction is used to prepare

Answer»

R-F
R-Cl
R-Br
R-I

Answer :D
Discussion
34.

For making tyres,___is added to natural rubber during vulcanization.

Answer»

1%-3% sulphur
3%-10% sulphur
20%-30% sulphur
30%-50% sulphur

Answer :B
Discussion
35.

Friedel crafts reaction is an example of ........... catalysis.

Answer»

SOLUTION :HETEROGENEOUS
Discussion
36.

Fridel-crafts' reaction of bromobenzene with methyl iodide gives

Answer»

o-bromotoluene
p-bromotoluene
o- and p-bromotoluenes
m-bromotoluene

Answer :C
Discussion
37.

Friedel-Crafts reaction of benzene with isobutyl chloride produces

Answer»

isobutylbenzene
tert-butylbenzene
n-butylbenzene
sec-butylbenzene.

Solution :`underset("ISOBUTYL CHLORIDE")(CH_(3)-OVERSET(CH_(3))overset("|")"CH"-CH_(2)Cl)overset(AlCl_(3))underset(-AlCl_(4)^(-))rarr CH_(3)-overset(CH_(3))overset("|")underset("H ")underset("|")"C "-overset(+)CH_(2)`
`overset("1,2-hydride")underset("shift")rarr CH_(3)-overset(CH_(3))overset("|")underset(CH_(3))underset("|")(C^(+))overset(C_(6)H_(6))underset(-H^(+))rarr underset("tert - butylbenzene")(CH_(3)-overset(CH_(3))overset("|")underset(CH_(3))underset("|")"C "-C_(6)H_(5))`
Discussion
38.

Friedel-Crafts acylation requires an excess of the catalyst but Fredel-Crafts alkylation requires only a catalytic amount. Why?

Answer»

Solution :The product of ACYLATION co-ordinates with the catalyst and removes the latter from the reactant side and thereby stops further acylation. For this reason, Friedel-Crafts acylation requires an excess of the catalyst. The product of alkylation does not co-ordinate with the catalyst. So, the catalyst can FORM COMPLEX with the alkylating agent and the catalyst PROPAGATES the reaction.
Discussion
39.

Friedel Crafts alkyation of benzene is an example of :

Answer»

nucleophilic substitution reaction
ELECTROPHILIC substitution reaction
electrophilic ADDITION reaction
FREE RADICAL substitution reaction

Answer :B
Discussion
40.

Friedel Craft's acylation.

Answer»

Solution :Friedel CRAFT's ACYLATION : The introduction of acyl group
in the BENZENE ring is termed as Friedel Craft's acylation. Anhydrous
`AlCl_(3)` is used as the catalyst.
Chlorobenzene react with acetyl CHLORIDE in presence of
anhudrous aluminium chloride to form o- and p-chloro acetophenones.
Discussion
41.

Friedel Craft acetylation of chlorobenezene gives

Answer»

3-chloroacetophenone
2-chloroacetophenone
1-(4-chlorophyenyl) ethanone
1-(3-chlorophenyl) ethanal

Answer :C
Discussion
42.

Freundlich equation for adsorption of gases (in amount of x g) on a solid (in amount of m g) at constant temperature can be expressed as

Answer»

`LOG(x)/(m)=LOGP+(1)/(n)logK`
`log(x)/(m)=logK+(1)/(n)logp`
`(x)/(m)propp^(n)`
`(x)/(m)-logp+(1)/(n)logK`

SOLUTION :According to FREUNDLICH equation,
`(x)/(m)propp^((1)/(n))or, (x)/(m)=Kp^((1)/(n))`
or `log(x)/(m)=logKp^((1)/(2)) or log(x)/(m)=logK+(1)/(n)logp`.
Discussion
43.

Freundlich adsorption isotherm is given by the expression (x)/(m)=kp^((1)/(n)). Which of the following conclusions can be drawn from this expression ?

Answer»

<P>When `(1)/(n)=0`, the adsorption is independent of pressure. 
When `(1)/(n)=0`, the adsorption is directly proportional to pressure.
When `n=0,(X)/(m)`, VS p-graph is a line parallel to X-axis. 
When `n = 0`, plot of `(x)/(m)` vs p is a curve. 

Solution :`(x)/(m)=K.p^((1)/(n))`
If `(1)/(n)=0”“therefore(x)/(m)=k`
If `n=0”“therefore` Plot is parallel to X-axis
Discussion
44.

Freundlich adsorption isothermal equation is applicable fo adsorption of ..........

Answer»

SOLUTION :GASES on solidsurface
Discussion
45.

Freundlich adsorption isotherm x//m = kp^(1//n) may be graphically represented as

Answer»




SOLUTION :
Discussion
46.

Freundlich adsorption isotherm is (x)/m = kp^((1)/n where n gt1. Anser the following questions based on Freundlich adsorption isotherm: What is adsorption isotherm?

Answer»


ANSWER :The relationship between EXTENT of adsorption of a GAS and pessure is called adsorption ISOTHERM.
Discussion
47.

Freundlich adsorption isotherm is given by the expression x/m=k p^(1/n). Which of the following conclusions can be drawn from this expression ?

Answer»

When `1/n=0,` the adsorption is independent of PRESSURE
When `1/n=0,` the adsorption is directly proporational to pressure
When `n=0,x/m` vs p graph is a line parallel to x-axis
When `n=0,` PLOT of `x/m` vs p is a curve

Solution :`x/m=kp^(1/n).` When `1/n=0,x/m=kp^(0)=k` (constant) i.e., it becomes independent of pressure. HENCE, (a) is CORRECT and (b) is wrong. When `n=0, x/m=k p^(oo).` Hence,` x/mvsp` cannot be linear parallel to x-axis but will be a curve. Hence, (c ) is wrong and (d) is correct.
Discussion
48.

Freundlich adsorption isotherm is given by the expression (x)/(m) = kp^((1)/(n)). Then the slope of the line in the following plot is

Answer»

<P>`SQRT(N)`
`1//n`
`x//m`
`p`

ANSWER :B
Discussion
49.

Freundlich adsorption isotherm is:

Answer»

<P>`(x )/(m) = kp ^(N)`
`k = (x)/(m) p ^(1//n)`
`(x)/(m) = kp ^(1//n)`
`(m)/(x) = kp ^(1//n)`

ANSWER :C
Discussion
50.

Freshly prepared precipitates can be easily dispersed by shaking it with dispersion medium. The process is called:

Answer»

PEPTISATION
Electrophoresis
Dispersion
Dialysis.

Answer :A
Discussion