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.

The additive used to make PVC, a flexible plastic is called

Answer»

ANTIOXIDANT
PLASTICISER
STABILIZER
Synthesier

ANSWER :B
Discussion
2.

The addition product is obtained by reaction between alkene and diborane. This reaction is called ..

Answer»

ACID catalysed hydration
Reduction of alkene
Oxidation of alkene
HYDROBORATION REACTION

Solution :Hydroboration reaction
Discussion
3.

'The addition of unsymmertial reagent to unsymmetrical alknes occurs in such a way that the negative part of the addendum goes to that carbon atom of the double bond which carreis lesser number of hydrogen atoms'' is called by

Answer»

Saytzeff rule
Markownikoff's rule
Kharasch effect
Anti-saytzeff rule

Solution :Accroding to Markownikoff's rule, the negative part of the unsymmetrical reagent ADDS to LESS hydrogenated (more substituted) carbon atom of the DOUBLE bond.
I `HX hArrH^(+)+,X^(-)`
Discussion
4.

The addition of the salt CH_(3)COONa to a solution of CH_(3)COOH result in a decrease of the initial

Answer»

`[OH^(-)]`
`[CH_(3)COO^(-)]`
`[H^(+)]`
`[Na^(+)]`

Answer :C
Discussion
5.

The addition of pure solid sodium carbonate to pure water causes………

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an increase in HYDRONIUM ion concentration
an increase in alkalinity
No change in acidity
A decrease in hydroxide ion

Solution :Adding `Na_2CO_3` to water makes the solution BASIC and hence pH INCREASES from 7
Discussion
6.

The addition of solid sodium carbonate to pure water causes :

Answer»

INCREASE in `H^(+)` ion concentration
DECREASE in pH
an increase in pH
no CHANGE in pH

Solution :The solution of sodium CARBONATE is alkaline and, therefore, pH increases.
Discussion
7.

The addition of pure solid sodium carbonate to pure water causes ………….. .

Answer»

an increase in HYDRONIUM ion concentration
an increase in alkalinity
No change in acidity
A decrease in HYDROXIDE ion

Solution :Hint : Adding `Na_(2)CO_(3)` to WATER makes the solution basic and hence pH INCREASES from 7.
Discussion
8.

The addition of one of the reactants in a reaction at equilibrium

Answer»

ALWAYS SHIFTS the equilibrium towards product at constant volume but not always at constant PRESSURE
always shifts the equilibrium towards product at constant pressure but not always at constant volume
always shifts the equilibrium towards product EITHER at constant pressure or at constant volume
does not shift the equilibrium either at constant pressure or at constant volume

Answer :A
Discussion
9.

The addition of metal like Cr, Mn W and Ni to ordinary steel makes it

Answer»

More useful
Alters the PROPERTIES of ORDINARY steel
Both (a) and (b)
NONE of these

Answer :C
Discussion
10.

The addition of K_(2)CO_(3) (aq) to the following solution is expected to produce a precipitate in every case but that one which does not produce precipitate is:

Answer»

`BaCl_(2) (aq)`
`CaCr_(2) (aq)`
`Na_(2)SO_(4) (aq)`
`Pb(NO_(3))_(2)(aq)`

Solution :N//A
Discussion
11.

The addition of HI in the presence of peroxide does not show anti-Markovnikov behavior because

Answer»

the HI band is too strong not to be broken homolytically
HI is reducing agent
I free radical so formed readily combine with each other to give `I_(2)` MOLECULE
I comine with H to give back HI

Solution :H-I bond is WEAK (71/Kcal/mole) BREAKS homolytcically 1 free radical, it so formed combine each other PRODUCES `I_(2)` molecule.
Discussion
12.

The addition of HOCl with unsymmetrical alkenes produces the product X as R-CH =CH_2 + HOClrarrX. Therefore ,the product X is :

Answer»

`R - CH(OH) - CH_2Cl`
`R-CH(CL)-CH_2OH`

ANSWER :A
Discussion
13.

The addition of HCN to carbonyl compounds is an example of .............. reaction.

Answer»

NUCLEOPHILIC substitution
Electrophilic ADDITION
Nucleophilic addition
Electrophilic substitution

Solution :Nucleophilic addition
Discussion
14.

The addition of HCl will not suppress the ionization of

Answer»

Acetic ACID
BENZOIC acid
`H_(2)S`
Sulphuric acid

Solution :COMMON ION effect is noticed only for weak ELECTROLYTE dissociation. `H_(2)SO_(4)` is strong electrolyte.
Discussion
15.

The addition of HCN to carbonyl compounds is an example of

Answer»

nucleophilic ADDITION
electrophilic addition
FREE radicaladdition
elimination addition.

Solution :
NUCLEOPHILE attacks at the positive C CENTRE of carbonyl group hence the addition is nucleophilic addition.
Discussion
16.

The addition of HCl in propene proceeds via

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`CL^(+)` in first stpe
`H^(+)` in first step
`H^(-)` in first step
`Cl^(+) and H^(+)` in single step

Solution :Since oxygen is more ELECTRONEGATIVE than cl, therefore, heterolytic of HO-Cl gives `HO^(-) and Cl^(+)`. Since alkene UNDERGOES `E^(+) AR,` therefore the electrophilic `Cl^(+)` attack first to generate more stable carboncation, which then undergoes mcleophilic attackby `OH^(-)` to give propylene chlorohydrine
`CH_(3)-CH=CH_(2)+Cl^(+) to CH_(3)- overset(o+)(CH)-CH_(2)Cl`
Discussion
17.

The addition of HCl in presence of peroxide does not follow anti-Markovnikov's rule because

Answer»

HCL BOND is too strong to be BROKEN homolytically
CI atom is not reactive enough to add on to a double bond
Cl atom combines with H atom to form HCI
HCl is a reducing agent.

Solution :The second propagating STEP involving the homolytic eleavage of HCl is endothermic.
Discussion
18.

The addition of HCl does not suppresses the ionisation of :

Answer»

ACETIC ACID
Benzoic acid
`H_2S`
`H_2SO_4`

ANSWER :D
Discussion
19.

The addition of HBr to 2-pentene gives

Answer»

2-bromopentane only
3-bromopentane only
2-bromopentane and 3-bromopentane
1-bromopentane and 3-bromopentane

Solution :`CH_3-CH_2-CH=CH-CH_3overset(H^+)to CH_3-CH_2-CH_2-overset+CH-CH_3 "and" CH_3-CH_2-overset+CH-CH_2-CH_3`
Discussion
20.

The addition of HBr on butene-2 is an example of:

Answer»

NUCLEOPHILIC addition
Free RADICAL addition
Electrophilic addition
None of these

Answer :C
Discussion
21.

The addition of HBr on butene-2 in presence of peroxide follow the:

Answer»

ELECTROPHILIC addition
Free RADICAL addition
Nucleophilic addition
None of the above

Answer :B
Discussion
22.

The addition of four amine groups to a metal ion (X^(2+)) shows a stability constants of 2 * 10^4, 1.5 * 10^3, 1.2 * 10^2 and 1.4 * 10^1 respectively. Then, the overall complex dissociation equlolibrium constant for [X(NH_3)_4]^(2+) ion is

Answer»

5.04 * 10^(-10)`
19.8 * 10^(-10)`
1.98 * 10^(-11)`
50.4 * 10^(-9)`

ANSWER :C
Discussion
23.

The addition of ferric hydroxide solution to arseneous sulphide solution results in the precipitation ofboth.

Answer»

Solution :This is possible only in CASE equimolar solutions (solutions with same number of MOLES) are mixed. Since the ferric hydroxide sol carries positive CHARGE and arsenic oxide sol is negatively charged on MIXING they will get their charge neutralized and will be COAGULATED.
Discussion
24.

The addition of excess of aqueous HNO_(3) to a solution containing [Cu(NH_(3))_(4)]^(2+) produces

Answer»

`CU^(+)`
`[Cu(H_(2)O_(4))]^(2+)`
`Cu(OH)_(2)`
`Cu(NO_(3))_(2)`

Answer :B
Discussion
25.

The addition of bromine to cyclopentene provides evidence for bromonium ion intermediate in bromine addition. It follows ionic mechanism. When cyclopentene reacts with bromine in presence of. "CC"l_4 anti addition occurs and gives trans isomer. So, addition of halogen to an alkene is a stereospecific reaction. Cis alkene on addition with halogen gives racemic products and trans alkene on addition gives meso mixture. Trane 2-butene on reacting with Br_2 in CCl_4 forms mainly

Answer»

`+-2,3-`DIBROMOBUTANE
`+2, 3-`dibromobutane
`-2,3-`dibromobutane
Meso 2, 3-dibromobutane

Answer :(D)
Discussion
26.

The addition of catalyst during a chemical reaction alters which of the following quantities?

Answer»

Enthalpy
Activation energy
ENTROPY
Internal energy

Solution :When catalyst is ADDED, the reaction follows a NEW PATH with lower activation energy.
Discussion
27.

The addition of bromine to cyclopentene provides evidence for bromonium ion immediate in bromine addition. It follows ionic mechanism. When cyclopentene reacts with bromine in presence of CCl_4 anti addition occurs and gives trans isomer so addition of halogen to an alkene is a stereospecific reaction. cis alkene on addition with halogen gives racemic mixture and trans álkene on addition may give meso products. trans-2-butene on reaction with Br_2 in C Cl_4 forms mainly

Answer»

`+-2,3-` DIBROMOBUTANE
`+2, 3-`dibromobutane
`-2,3-`dibromobutane
Meso 2, 3-dibromobutane

Answer :D
Discussion
28.

The addition of Br_(2) to Z-2-butane gives

Answer»

(R,R)-2,3-dibromo BUTANE only
(S-S)-2,3-dibromo butane only
(R,S)-2,3-dibromo butane only
A MIXTURE of (R R) and (S S)-2,3-dibromo butane (50%:50%)

ANSWER :D
Discussion
29.

The addition of Br_2 to (E)-but-2-ene gives

Answer»

(R,R)-2-3-DIBROMOBUTANE
( S,S)-2,3- dibromobutane
(R,S)-2,3- dibromobutane
A MIXTURE of (R,R) and (S,S-2,3)- dibromobutane

Solution :
Discussion
30.

The addition of Br_2 to ( E)-but-2-ene gives

Answer»

(R,R)-2-3-DIBROMOBUTANE
(S,R)-2-3-dibromobutane
(R,S)-2-3-dibromobutane
A MIXTURE of (R,R) and (S,S) 2,3 dibromobutane

ANSWER :C
Discussion
31.

The addition of a polar solvent to a solenoid electrolyte results in

Answer»

Polarization
Association
Ionization
Electron transfer

Solution :Polar solvent FACILITATE ionisation of STRONG ELECTROLYTES due to dipole-ion ATTRACTION.
Discussion
32.

The addition of aldehyde group to aromic molecules of phenol when it react with sodium hydroxide and chloroform is known as ...... Reaction.

Answer»

Kolbe-Schmitt
Reimer-Tiemann
Williamson's
Fries rearrangment

Solution :Reimer-Tiemann
Discussion
33.

The additionof ammonium chlorode to a solutioncontainingferric andmagnessiumions is easentialfor solectiveprecipitate offerric hydroxide by aqueous ammonium

Answer»


Solution :The ADDITION of AMMONIUM chloride to a solution containingferric and magnessium IONS isessential for selectiveprecipitate of ferric hydroxide byaqueous AMMONIA.
Discussion
34.

The addition of a polar solvent to a solid electrolyte

Answer»

POLARIZATION
ASSOCIATION
Ionization
NON- liberation of heat

Solution :When polar solvent ADDED in to solid ELECTROLYTE than it ionised.
Discussion
35.

The addition of acidic K_(2)Cr_(2) O_(7) to NaCl produces a colour

Answer»

green
PINK
RED
violet

ANSWER :C
Discussion
36.

The addition of a drop of copper sulphate solution to an alkaline solution of biuret gives:

Answer»

RED colour
VIOLET colour
green colour
ORANGE colour

Answer :B
Discussion
37.

The addition of 3g of a substance to 100g C CI_(4)(M = 154 g mol^(-1)) raises the boiling point of C CI_(4) by 0.60^(@)C if K_(b)(C CI_(4)) is 5K mol^(-1) kg, calculate (a) the freezing point depression (b) the relative lowering of vapour pressure (c) the osmotic pressure at 298K and (d) the molar mass of the substance. Given: K_(f) (C CI_(4)) = 31.8 K kg mol^(-1) and rho (solution) = 1.64 g cm^(-3)

Answer»


Solution :(a) `(DeltaT_(f))/(DeltaT_(b)) = (K_(f))/(K_(b))`
`DeltaT_(f) = (31.8)/(5.03) XX 0.6 = 3.79^(@)C`
(b) `m = (DeltaT_(b))/(K_(b)) = (0.6)/(5.03) = (x xx1000)/((1-x)154)`
`rArr 1-x = 54.44 x`
`rArr 55.44 x = 1`
`x = (DeltaP)/(P^(@)) = (1)/(5.44) = 0.018`
(c) `(1)/(55.44) = ((3)/(M_(1)))/((3)/(M_(1))+(100)/(154))`
`rArr (100)/(154) = (166.32)/(M_(1)) M_(1) = 231.5`
`M = (0.6)/(5.03)`
`(M xx 1000)/(1000 xx 1.64 -M xx 251.5)`
`1640 = 8634.83M`
`M = 0.19`
`p = n//V RT = 0.19 xx 0.0821 xx 298`
`=4.65 atm`
Discussion
38.

The addition of a catalyst during a chemical reaction alters which of the following quantities ?

Answer»

Activation energy
ENTROPY
Internal energy
Enthalpy

ANSWER :A
Discussion
39.

The addition of 41.2mg of an unkown alcohol ROH to CH_(3)MgI releases 1.56mL of a gas at STP. The molar mass of the gas is

Answer»

32 g `mol^(-1)`
46 g `mol^(-1)`
59 g `mol^(-1)`
74 g `mol^(-1)`

SOLUTION :
Discussion
40.

The addition of 3 gms of a substance to 100 gms C Cl_(4) (M.w. = 154 gm/mole) raises the boiling point of C Cl_(4) by 0.60^(@)C. If K_(b) of C Cl_(4) is 5.03 K Kg "mole"^(-1) then find out the relative lowering of vapour pressure.

Answer»

`0.0181`
`0.0224`
`0.204`
`0.192`

SOLUTION :Substance = 3 gms `= W_(2)`
Mol. Wt. of sub `= M_(2)=?`
SOLVENT `= C Cl_(4)=100 gms = W_(1)`
Molal of solvent `C Cl_(4)=153" gm mole"^(-1)=M_(1)`
Increase of B.P. `= Delta T_(b)=0.6^(@)C`
`K_(b)` of solvent `C Cl_(4)=5.03" K kg mole"^(-1)`
`M_(2)=(K_(b)xx W_(2)xx 100)/(Delta T_(b)xx W_(1))`
`therefore M_(2) = (5.03xx3xx1000)/(0.6xx100)`
`= 251.5"gm mol"^(-1)`
Relative depression of vapour pressure
`= (p^(@)-p)/(p^(@))=X_(2)`
`= (n_(2))/(n_(1)+n_(2))`
Where `n_(2)=` mole of solvent
`= (W_(2))/(M_(2))=(3)/(251.5)`
= 0.0119 mole substance
`n_(1)=` mole of solvent
`= (W_(1))/(M_(1))=(100)/(154)`
= 0.6494 mole solvent `C Cl_(4)`
TOTAL mole `= 0.6494+0.0119=0.6613`
`X_(2)=(0.0119)/(0.6613)`
`=0.01799 ~~0.0181`
Discussion
41.

The addition of 3 gm of substance to 100gm C Cl_(4) (M=154 gm "mol^(-1)) raises the boiling point of C Cl_(4) by 0.6^(@)C. K_(b)(C Cl_(4)) is5.03d kg "mol"^(-1)K, K_(f)(CCl_(4)) is31.8 kg "mol"^(-1)K and dencity of solution is 1.64 gm/ml . The molar mass of the substance is :

Answer»

`37.9`
18
46.5
251.5

Answer :D
Discussion
42.

The addition of 3 gm of substance to 100gm C Cl_(4) (M=154 gm "mol^(-1)) raises the boiling point of C Cl_(4) by 0.6^(@)C. K_(b)(C Cl_(4)) is5.03d kg "mol"^(-1)K, K_(f)(CCl_(4)) is31.8 kg "mol"^(-1)K and dencity of solution is 1.64 gm/ml . Calculate the depression in freezing point

Answer»

`3.79^(@)C`
`0.018^(@)C`
`4.65^(@)C`
`251.5^(@)C`

ANSWER :A
Discussion
43.

The additio of HBr to but-1-ene gives a mixture of products (I),(II) and (III). . (III). CH_(3)-CH_(2)-CH_(2)-CH_(2)-Br. Mixture consists of

Answer»

(I) and (II) as MAJOR and (III) as MINOR PRODUCTS
(II) as major, (I) and (III) as minor products.
(II) as minor, (I) and (III) as major products.
(I) and (II) as minor and (III) as major products.

Solution :
Discussion
44.

The addition of 3 gm of substance to 100gm C Cl_(4) (M=154 gm "mol^(-1)) raises the boiling point of C Cl_(4) by 0.6^(@)C. K_(b)(C Cl_(4)) is5.03d kg "mol"^(-1)K, K_(f)(CCl_(4)) is31.8 kg "mol"^(-1)K and dencity of solution is 1.64 gm/ml . The Osmotic pressure at 298K is :

Answer»

`3.79 ` ATM
`0.018` atm
`4.65` atm
`251.5` atm

ANSWER :C
Discussion
45.

The addition homopolymers are :

Answer»

STYRON
PMMA
Terylene
Bakelite

Answer :A::B::D
Discussion
46.

The addictive property of narcotic drugs is mainly due to their ability to produce

Answer»

EUPHORIA
BLOOD clotting
Mental disorderd
Hyper acidity

Solution :NARCOTICS PRODUCE euphoria
Discussion
47.

The actual order of reactivity ofalkyl halide is

Answer»

`R-CL GT R-Br gt R-I`
`R-I gt R-Br gt Cl`
`R-Br gt R-Cl gt RI`
`R-I gt R-Cl gt R-Br`

ANSWER :B
Discussion
48.

The actual electron confuguration of La(Z=57) is ….

Answer»

`[Xe] 4F^(1)5d^(0)6s^(2)`
`[Xe] 4f^(3)`
`[Xe] 4f^(0)5d^(1)6s^(2)`
`[Xe] 4f^(0)5d^(3)`

Solution :`[Xe] 4f^(0)5d^(1)6s^(2)`
Discussion
49.

The actual density of nitrogen is 1.2519 "lit"^(-1) . The density of nitrogen obtained from the atmosphere is 1.2572 g "lit"^(-1) . This is because of the fact that atmospheric nitrogen contain

Answer»

ARGON and other NOBLE gases
Carbon dioxide
Neon
Carbon monoxide

Answer :A
Discussion
50.

The activity per ml of a solution of radioactive substances is x.How much water be added to 200 ml of this

Answer»


Solution :In solution,`x_A=0.3, x_B=0.7`
In VAPOUR PHASE, `x'_A=0.6,x'_B=0.4`
`x'_A=p_A/P=0.6`
`p_A/(p_A+p_B)=(p_A^@x_A)/(p_A^@x_A+p_B^@x_B)`
`0.6=(0.3p_A^@)/(0.3p_A^@+0.7p_B^@)`…(1)
`x'_B=p_B/P=p_B/(p_A+p_B)=0.4`
`IMPLIES (0.7p_B^@)/(0.3p_A^@+0.7p_B^@)=0.4`...(2)
DIVIDING (1) by (2)
`(0.3p_A^@)/(0.7p_B^@)=0.6/0.4`
`implies p_A^@/p_B^@=(0.6xx0.7)/(0.4xx0.3)=7/2=3.5`
Discussion