Explore topic-wise InterviewSolutions in .

This section includes InterviewSolutions, each offering curated multiple-choice questions to sharpen your knowledge and support exam preparation. Choose a topic below to get started.

84751.

Adsorption phenomenon involves (A) residual attraction forces (B) a spontaneous phenomenon (C) a gaseous adsorbent

Answer»

A and C are CORRECT
B and C are correct
A and B are correct
A, B and C are all correct

Answer :C
Discussion
84752.

Which ismore basic, aliphatic amines or ammonia and why ?

Answer»


ANSWER :T
Discussion
84753.

Aliphatic amines are …..basic than NH_3 but aromatic amines are ……basic than NH_3

Answer»

More ,less
Less, more
BOTH (A) AND (B)
NONE

ANSWER :A
Discussion
84754.

Aliphatic aldehydes react with Fehling's solution to give red ppt, but benzaldehyde does not produce red precipitate with Fehling's solution because :

Answer»

Of a BULKY ring - CHO is hinderer
Of resonance , oxidation of BENZALDEHYDE
(-CHO) is present in cyclic STRUCTURE
Of all the above statement

Answer :B
Discussion
84755.

Adsorption of N_(2) gas on iron at 83 K is ………. Whereas at 773 K, it is …….(fill in the type of adsorption).

Answer»

SOLUTION :PHYSISORPTION, chemicorption
Discussion
84756.

Aliphatic aldehydes do not show______isomerism.

Answer»

SOLUTION :POSITION.
Discussion
84757.

Aliphatic aldehyde except ................... react with an ethereal solution of ammonia to form aldimines.

Answer»

SOLUTION :FORMALDEHYDE
Discussion
84758.

Find out the correct pair (a)Limonite-Sulphide ore (b)Cuprite-Oxide ore (c )Calamine-Sulphide ore (d)Horn silver-Oxide ore

Answer»

SOLUTION :(B)Cuprite-Oxide ORE
Discussion
84759.

Alimate is

Answer»

sedative
antioxidant
sweetener
preservative

Answer :C
Discussion
84760.

Adsorption of gases on solid surfaces is exothermic reaction because

Answer»

FREE energy increases
ENTHALPY is positive
Entropy increases
Enthalpy is negative

Solution :Adsoption is ACCOMPANIED by EVOLUTION of heat as the residual forces acting along the surface of adsorbent decrease i.e., ADSORPTION is accopanied by decrease in enthalpy.
Discussion
84761.

Alicyclic compounds are:

Answer»

AROMATIC compounds
aliphatic CYCLIC compounds
hetercyclic compounds
NONE of the above.

ANSWER :B
Discussion
84762.

Adsorption of gases on solid surface is generally exothermic because (IIT Screening)

Answer»

Enthalpy is positive 
Entorpy decreases 
Entropy increases 
FREE energy increases 

SOLUTION :In adsorption PROCESS `Deltas =-ve `
Discussion
84763.

Alguld is found to scatter a beam of light but leaves no residue when passed through the filter paper. The liquid can be described as:

Answer»

a suspension
a TRUE SOLUTION
a COLLOIDAL solution
oil,

ANSWER :C
Discussion
84764.

AlF_(3)is soluble in HF only in presence of KF. It is due to the formation of

Answer»

`AlH_(3)`
`K[AlF_(3)H]`
`K_(3)[AlF_(3)H_(3)]`
`K_(3)[AlF_(6)]`

SOLUTION :`AlF_(3) + 3KF to K_(3)[AlF_(6)]`
Discussion
84765.

Adsorption of gases on solid surface is generally an exothermic process because

Answer»

FREE ENERGY INCREASES
ENTROPY decreases
Enthalpy is positive
Entropy increases.

Answer :B
Discussion
84766.

AlF_(3) isinsolublein andydrous HFbutwhen little KFisaddedto thecompoundsitbecomessolubleOnadditionof BF_(3),AlF_(3)is precipitate write thebalancedchemicalequation .

Answer»

Solution :Anltydrous `HF` is stabiliused dueto intermolecular H-bonding and is less DISSOCIATED `AIF_(3)` is soluble in `HF` in the PRESSENCE of `KF` dueto THEFORMATIONOF `[AIF_(6)]^(3-): 3KF + AIF_(3) rarr K_(3)[AIF_(6)]`
`BF_(3)` displacesour `F^(Theta) ` from `[AIF_(6)]^(3-)` because it is more acidic than`AIF_(3)`
`K_(3) [AIF_(6)] + BF_(3) rarr AIF_(3) DARR+ 3KBF_(4)`
Discussion
84767.

Adsorption of a gas on the surface of solid is generally accompanied by decrease in entropy. Still it is a spontaneous process. Explain.

Answer»

Solution :WHETHER or not, a process occurs, is decided by `DeltaG ` value which should be NEGATIVE. In ADSORPTION, `DeltaS` is -ve, but `DeltaH ` is also -ve because it is an EXOTHERMIC process.
`DeltaG=DeltaH-TDeltaS`
The NET value of `DeltaG` is negative. Hence, it is a spontaneous process.
Discussion
84768.

Alexander Williamson prepared diethyl by a simple method, now called as Williamson's ether synthesis . In this method, an alkyl halide is treated with sodium alkoxide prepared from sodium and alcohol. This reaction is used in the synthesisof symmetrical and unsymmetrical ethers. It may be noted taht for preparing unsymmetrical ethers, the halide used should preferably be primary because secondary and tertiary alkyl halides may form alkenes as major product due to elimination process. CH_(3)-underset(CH_(3))underset(|)overset(CH_(3))overset(|)(C)-Br+underset("Sodium ethoxide")(Na^(+)O^(-)-C_(2)H_(5))rarrunderset("2-methylpropene")(CH_(3)-overset(CH_(3))overset(|)(C)=CH_(2))+C_(2)H_(5)OH+NaBr Aryl ethers or phenolic ethers can be prepared by using sodium phenoxide and alkyl halides. However, aryl halides and sodium alkoxide cannot be used for preparing phenolic ethers because aryl halides are less reactive towards nucleophilicsubstitution reaction There are two possibilities for the synethesis of following ether : Which of the following is correct ?

Answer»

ROUTE 1 GIVES REQUIRED ether
Route 2 gives required ether
Both route 1 and route 2 give the required ether
None of the route is correct

Answer :B
Discussion
84769.

AlF_3 is an ___________ compound, but AlCl_3 is a__________compound.

Answer»

SOLUTION :IONIC, COVALENT
Discussion
84770.

Alexander Williamson prepared diethyl by a simple method, now called as Williamson's ether synthesis . In this method, an alkyl halide is treated with sodium alkoxide prepared from sodium and alcohol. This reaction is used in the synthesisof symmetrical and unsymmetrical ethers. It may be noted taht for preparing unsymmetrical ethers, the halide used should preferably be primary because secondary and tertiary alkyl halides may form alkenes as major product due to elimination process. CH_(3)-underset(CH_(3))underset(|)overset(CH_(3))overset(|)(C)-Br+underset("Sodium ethoxide")(Na^(+)O^(-)-C_(2)H_(5))rarrunderset("2-methylpropene")(CH_(3)-overset(CH_(3))overset(|)(C)=CH_(2))+C_(2)H_(5)OH+NaBr Aryl ethers or phenolic ethers can be prepared by using sodium phenoxide and alkyl halides. However, aryl halides and sodium alkoxide cannot be used for preparing phenolic ethers because aryl halides are less reactive towards nucleophilicsubstitution reaction Select the correct reaction (s) among the following reactions :

Answer»




ANSWER :A,D
Discussion
84771.

Adsorption of gases on solid surface is an exothermic eaction because

Answer»

FREE energy increases
enthalpy is positive
entropy increases
enthalpy is negative.

Solution :During adsorption, there is ALWAYS a decrease in residual forces of the surface i.e., there is decrease in surface energy which APPEARS as heat. Adsorption THEREFORE is invariably accompanied by evolution of heat i.e., it is an exothermic PROCESS.
Discussion
84772.

Aldoxime on oxidation by trifluoroperoxy acetic acid gives

Answer»

`1^(@)`- AMINES
`2^(@)` - amines
`1^(@)`- NITROPARAFFINS
`2^(@)` - nitroparaffins

Answer :C
Discussion
84773.

Aldoximeon reduction withNa + C_(2)H_(5)OHform

Answer»

`1^(0)`AMINES
`2^(0)` amines
`3^(0)`amines
ALCOHOLS

Solution :Aldoximeor KETOXIMEON reductiongivesonly`1^(@)`amines.
Discussion
84774.

Adsorption of gases in solid surface is generally exotheric because

Answer»

Enthalpy is positive
Entropy DECREASES
Entropy increases
Free energy increase

Solution :Due to RANDOMNESS of particles is REDUCED SINCE entropy decreases.
Discussion
84775.

Aldotetroses consist of two different chiral carbon atoms and they exist in

Answer»

2 OPTICALLY ACTIVE forms
4 optically active forms
6 optically active forms
8 optically active forms

Answer :B
Discussion
84776.

Adsorption of a gas on the surface of solid is generally accompanied by decrease in entropy. Still it is a spontaneous process. Explain

Answer»

Solution :Adsorption is an exothermic PROCESS, i.e., energy factor favours the process. As `Delta G = Delta H - T Delta S` ,in adsorption, THOUGH `Delta S`is -ve but `Delta H`is also -ve and `Delta H GT T Delta S`in magnitude so that `Delta G`is -ve. Hence, the process is SPONTANEOUS
Discussion
84777.

Aldopentoses named as ribose and 2-deoxyribose are found in nucleic acids. What is their relative configuration ?

Answer»

SOLUTION :D-configuration.
Discussion
84778.

Adsorption of a gas on solid metal surface is spontaneous and exothermic , then .....................

Answer»

`DELTAH` increases
`DELTAS` increases `
`DELTAG` increases
`DeltaS` DECREASES

Solution :`DeltaS` decreases `-DeltaS` is -ve.
Discussion
84779.

Aldol reaction is given by aldehydes and ketones having at least one

Answer»

`ALPHA-` HYDROGEN.
`BETA-` hydrogen.
`GAMMA-` hydrogen.
no hydrogen atom.

Answer :A
Discussion
84780.

Adsorption of a gas on the surface of a solid adsorbent is ……….(exothermic or endothermic or neither exothermic nor endothemic).

Answer»

SOLUTION :EXOTHERMIC
Discussion
84781.

Aldopentoses named as ribose and 2 - deoxyribose are found in nucleic acids. What is their relative configruations ?

Answer»

SOLUTION :The open CHAIN structure of ribose and 2- DEOXYRIBOSE are given. Both of them have D-configuration.
Discussion
84782.

Aldol is

Answer»

2-hydroxy butanol
3-hydroxy butanol
3-hydroxy BUTANAL
2-hydroxy butanal

Answer :C
Discussion
84783.

Adsorption of a gas follows Freundlich adsorption isotherm. In the given plot, x is the mass of the gas adsorbed on mass m of the adsorbent at pressure p. (x)/(m) is proportional to :

Answer»

<P>`p^(2)`
p
`p^(1//2)`
`p^(1//4)`

ANSWER :C
Discussion
84784.

Adsorption of a gas on solid metal surface is spontaneous and exothermic, then

Answer»

`DELTAH` INCREASES
`DELTAS` increases
`DELTAG` increases
`DeltaS` DECREASES

Solution :`DeltaS` decreases
Discussion
84785.

Aldol condensation will not be observed in

Answer»

CHLORAL
PHENYL ACETALDEHYDE
Hexanal
Ethanal

SOLUTION :Chloral does nothave any a-Hydrogen ATOM
Discussion
84786.

Adsorption isotherm of gases on solids give the relation between

Answer»

VOLUME of ADSORBENT and TEMPERATURE 
amount of adsorbent per unit weight of adsorbate and PRESSURE 
amount of adsorbate per unit weight of adsorbent and equilibrium pressure 
volume of adsorbate and pressure 

Answer :C
Discussion
84787.

Adsorption occurs at fixed sites called ............

Answer»

SOLUTION :activecentres
Discussion
84788.

Aldolcondensation will not be observed in

Answer»

chloral
phenylacetaldehyde
hexanal
None of the above

SOLUTION :Chloral does not contain an `alpha`-hydrogen atom, hence DOSE not undergo aldol condensation. Instead it undergoes hydrolysis to GIVE `CHCl_(3)`.
Hence, (A) is the correct ANSWER.
Discussion
84789.

Adsorption isotherms are properly represented as in

Answer»




ANSWER :C
Discussion
84790.

Aldol condensation takes place in:

Answer»

ACID medium
Basic medium
Neutral medium
None

Answer :B
Discussion
84791.

Adsorption is the tendency of accumulation of molecular species at the surface of solid or liquid. Depending upon the nature of bonds or forces of attraction between adsorbate and adsorbent. It is classofied between physisorption and chemisorption. Which of the following characteristics is not correct for physical adsorption?

Answer»

ADSORPTION is spontaneous. It is reversible in NATURE
Degree of adsorption increases with temperature

Solution :With increases of temperature ADSOPTION DECREASES.
Discussion
84792.

Aldol condensation reaction is a special reaction of aldehydes. (ii) Write the structural formula of aldol formed from ethanal.

Answer»


ANSWER :`(##ANE_PKE_CHE_XII_C12_E02_041_S01##)`
Discussion
84793.

Adsorption is the presence of excess concentration of any particular component at the surface of liquid a solid phase as compared to bulk.This is due to presence of residual forces at the surface of body.In the adsorption of hydrogen gas over a sample of charcoal, 1.12cm^3 of H_2(g) measured over S.T.P was found to absorb per gram of charcoal.Consider only monolayer adsorption.Density of H_2 is 0.07gm/cc. In another experiment same 1 gm charcoal adsorbs 100 ml of 0.5M CH_3COOH to form monolayer and thereby the molarity of CH_3COOH reduces to 0.49. ((3xx47.43)/(4pi))^(1//3)=2.24 (2.24)^2=5 Number of molecules of hydrogen over 1 gram charcoal are-

Answer»

`3.01xx10^(18)`
`3.01xx10^(19)`
`3.01xx10^(21)`
`3.01xx10^(22)`

Solution :VOLUME of `H_2` over 1 gm charcoal `=1.12 cm^2` at STP
mole of `H_2=1.12/22400=5xx10^(-5)` mole
Number of molecules of `H_2=5xx10^(-5)xx6.023xx10^(23)=3.01xx10^19` molecules
Discussion
84794.

Aldol condensation reaction is a special reaction of aldehydes. (i) What is aldol condensation reactions?

Answer»


ANSWER :REFER to THEORY
Discussion
84795.

Adsorption is multilayered in case of

Answer»

CHEMISORPTION
Desorption
Physical adsorption
Both chemissorption and desorption

Answer :C
Discussion
84796.

Aldol condensation product of the aldehyde Hexan-1,6-dial

Answer»

CYCLO PEN 1-ene 1-carbaldehyde
Cyclo HEXA 1-enal
Cyclo But 2-en 1-carbaldehyde
Cyclo Hexenal

Answer :A
Discussion
84797.

Adsorption is the phenomenon in which a substance

Answer»

ACCUMULATES on the SURFACE of other substance
Goes into the BODY of the other substance
Remains CLOSE to the other substance
Does not accumulates on the surface of the other substance.

Answer :A
Discussion
84798.

Aldol condensation proceeds by carbon-carbon bond formation between an enolate donor and a carbonyl acceptor. For each of thefollowing aldol products (a thorugh e) select a donor and an acceptor compound from the list at the bottom of the page (compounds A through H). write the letter corresponding to your selection in the appropriate answer box. . Q.

Answer»


SOLUTION :a-Donar=C,Acceptor=C,b-Donar=E,Acceptor=D,c-Donar=B,Acceptor=A,d-Donar=G,Acceptor=G,e-Donar=F,Acceptor=Bs
Discussion
84799.

Adsorption is exothermic/endothermic process.

Answer»

SOLUTION :EXOTHERMIC
Discussion
84800.

Aldol condensation proceeds by carbon-carbon bond formation between an enolate donor and a carbonyl acceptor. For each of thefollowing aldol products (a thorugh e) select a donor and an acceptor compound from the list at the bottom of the page (compounds A through H). write the letter corresponding to your selection in the appropriate answer box. . Q.

Answer»


SOLUTION :a-Donar=C,Acceptor=C,b-Donar=E,Acceptor=D,c-Donar=B,Acceptor=A,d-Donar=G,Acceptor=G,e-Donar=F,Acceptor=Bs
Discussion