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84801.	Adsorption is an exothermic process. Explain.
Answer»

84802.	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

84803.	Adsorption is always accompanied by decrease in ............
Answer» SOLUTION :FREE ENERGY

84804.	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

84805.	Adsorption is always multimolecular.
Answer» Solution :FALSE. PHYSISORPTION is MULTIMOLECULAR but chemisorption is UNIMOLECULAR.

84806.	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

84807.	Adsorption is always ....
Answer» ENDOTHERMIC exothermic Iso thermic either a (or) b Solution :endothermic

84808.	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. .
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

84809.	Aldol condensation of aldehydes and ketones takes place through the formation of:
Answer» Carbene Nucleophile Electrophile Free radical Answer :B

84810.	Adsorption is accompanied by:
Answer» DECREASE in ENTROPY of SYSTEM Decrease in ENTHALPY of the system `Ttriangles` for the PROCESS is negative All Answer :D

84811.	Aldol condensation involving CH_(3)CHO + CH_(3)CHO gives the product
Answer» `CH_(3)CHOHCH_(2)CHO` `CH_(3)COCH_(2)CH_(3)` `CH_(3)CH=CH_(2)` NONE of these Solution :`2CH_(3)CHO overset(NAOH)underset(dil)RARR underset(("Aldol"))(CH_(3)-underset(OH)underset(\|)(CH)-CH_(2))-CHO`

84812.	Aldol condensation is given by :
Answer» ALDEHYDES only having `alpha-H`atom Aldehydes and KETONES having `alpha-H` atom Ketones only having `alpha-H` atom Aldehydes having no `alpha-H` atom Answer :B

84813.	Aldol condensation does not occur between
Answer» two different aldehydes two different ketones an aldehydes and a ketone an aldehyde and an ester Solution :The `alpha`-hydrogens of an aldehyde `(pK_(a)~20)` are more acidic than those of an ester `(pK_(a)~25)`. Therefore, aldehydes form CARBANIONS more readily than esters. Further, due to +R-effect of OR group the ester carbonyl carbon is less electrophilic than that of an aldehyde. as a result, C=O of an aldehyde undergoes nucleophilic attach by the carbanion more readily than C=O of an ester. in other WORDS, aldol condensation does not OCCUR between an aldehyde and an ester.

84814.	Aldol condensation between which of the following two compounds followed by dehydration gives methyl vinyl ketone?
Answer» Formaldehyde and acetone Formaldehyde and acetaldehyde Two molecules of acetaldehyde Two molecules of acetone Solution :`UNDERSET("Formaldehyde")(CH_(2)=O)+underset("Acetone")(CH_(3)COCH_(3)) underset(("Cross aldol condensation"))OVERSET(OH^(-))to HOCH_(2)-CH_(2)-COCH_(3) underset(-H_(2)O)overset(H^(+)//H_(2)O,Delta)to underset("Methyl VINYL ketone")(CH_(2)=CH-CO-CH_(3))`.

84815.	Adsorption is a surface phenomenon. Discuss.
Answer»

84816.	Adsorption, if spontaneous, is exothermic.
Answer» Solution :Adsorption is ACCOMPANIED by DECREASE in entropy i.e., `DeltaS = -ve`. If it is spontaneous, `DELTAG` should be negative. `DeltaG = DeltaH - TDeltaS` SINCE `DeltaS` is negative (entropy decreases in the process of adsorption), `DeltaG` will be negative only if `DeltaH` is negative. That means the process will be EXOTHERMIC.

84817.	Adsorption has many applications. Write any two applications of adsorption.
Answer» Answer :Activated COCONUT charcol is used in gasmask to adsorp poisonous gases. SLICA gel is used to ADSORB water vapour and thus in removing moisute from air.

84818.	Aldol condensation between the following compounds followed by dehydration gives methyl vinyl ketone:
Answer» `HCHO` and `CH_3COCH_3` `HCHO` and `CH_3CHO` TWO MOLECULES of `CH_3CHO` Two molecules of `CH_3COCH_3` ANSWER :A

84819.	"Adsorbents in finely divided from are more effective ." Why ?
Answer» SOLUTION :DUE to their more SURFACEAREA in FINELY DIVIDED from .

84820.	Aldol condensation between the following compounds followed by dehydration gives methyl vinyl ketone :
Answer» METHANAL and ethanal TWO MOLE of formaldehyde Methanal and PROPANONE Two mole of ethanal Answer :C

84821.	Adsorbedhydrogen by palladium is called
Answer» NASCENT HEAVY ATOMIC OCCLUDED ANSWER :D

84822.	Aldol condensation.
Answer» Solution :When aldehydes or ketones containing `prop - H` atoms are warmed with a DILUTE base or dilute acid, TWO molecules of them undergo SELF CONDENSATION to give `beta-` hydroxy aldehyde (aldol) or `beta`- hydroxy ketone (KETOL) respectively.

84823.	Adsoption is an exothermic process. The amount of substance adsorbed should
Answer» decrease with decrease in temperature. decrease with INCREASE in temperature. decrease with decrease in temperature. no change with increase in temperature. Solution :Rate of adsorption increases with decrease in temperature because it is EXOTHERMIC process.

84824.	Aldol condensation of acetaldehyde involves the formation of which of the following intermediates
Answer» ACETATE ion a carbonium ion a CARBANION a FREE RADICAL Answer :C

84825.	Adolfvon Beeyersuggestedthat,sincecarbonprefers tohavetetradralgeometrv wih bondanglesof approximately109^(@)ring sizesotherthanfiveand six may betoostrainedto exist ,Baeyer based hishypothesison thesimplegeometricalnationthata three-memberedring ( cyclopropane ) shouldbe anequilatera trianglewithbond anglesto 60^(@) a fourmembered ring (cyclobutane) shouldbe asquarewithbondanglesof 90^(@) and so on . Accordingto Beayer'sanalysiscyclopropane, witha bondablecompressionof 109^(@)-60^(@)=49^(@) , shouldhavea large amountof anglestrainand mustthereforebehighlyreactive cyclohexane becomes puckeredtoreeveitsstrainthe angulardeviation ofcycloalkaneis (-11^(@)) , Greater is the angulardeviationmore is thetorsinalstrain . whichamongthe followinghasgreastest bond angle ?
Answer» cyclobutane cyclopentane cyclopentane cyclopropane Answer :D

84826.	Aldohexose reacts with acetone in H_(2)SO_(4) to form cyclic ketal. Necessary condition to form cyclic ketal is that two OH groups must be in cis (syn) position. Compound (D) reacts with 2 mol fo acetone to form cyclicdiketal, as shown below. Which statement(s) is//are correct about (E)?
Answer» Both CYCLIC KETALS have five-membered ring. Both cyclic ketals have six-membered ring. Cyclic ketals FORMED between `C-2` and `C-3` have five-membered ring. Cyclic ketals formed between `C-4` and `C-6` have six-membered ring. Answer :C::D

84827.	Adolfvon Beeyersuggestedthat,sincecarbonprefers tohavetetradralgeometrv wih bondanglesof approximately109^(@)ring sizesotherthanfiveand six may betoostrainedto exist ,Baeyer based hishypothesison thesimplegeometricalnationthata three-memberedring ( cyclopropane ) shouldbe anequilatera trianglewithbond anglesto 60^(@) a fourmembered ring (cyclobutane) shouldbe asquarewithbondanglesof 90^(@) and so on . Accordingto Beayer'sanalysiscyclopropane, witha bondablecompressionof 109^(@)-60^(@)=49^(@) , shouldhavea large amountof anglestrainand mustthereforebehighlyreactive cyclohexane becomes puckeredtoreeveitsstrainthe angulardeviation ofcycloalkaneis (-11^(@)) , Greater is the angulardeviationmore is thetorsinalstrain . whichof thefollowingcycloalkanehaszero strainenergy ?
Answer» cyclobutane cyclopentane cyclohexane cyclopropane Answer :C

84828.	Aldehydes with Tollen's reagent are
Answer» REDUCING agnet OXIDISING AGENTS hydrating agents BLEACHING agents ANSWER :A

84829.	Adolfvon Beeyersuggestedthat,sincecarbonprefers tohavetetradralgeometrv wih bondanglesof approximately109^(@)ring sizesotherthanfiveand six may betoostrainedto exist ,Baeyer based hishypothesison thesimplegeometricalnationthata three-memberedring ( cyclopropane ) shouldbe anequilatera trianglewithbond anglesto 60^(@) a fourmembered ring (cyclobutane) shouldbe asquarewithbondanglesof 90^(@) and so on . Accordingto Beayer'sanalysiscyclopropane, witha bondablecompressionof 109^(@)-60^(@)=49^(@) , shouldhavea large amountof anglestrainand mustthereforebehighlyreactive cyclohexane becomes puckeredtoreeveitsstrainthe angulardeviation ofcycloalkaneis (-11^(@)) , Greater is the angulardeviationmore is thetorsinalstrain . thetendency ofCyclopropropane (i) cyclobutane (ii) andcyclopentane (iii)to firm additioncompounds is intheorder:
Answer» IgtIIgtIII I=IIgtIII IgtII=III I=IIIgtI Answer :A

84830.	Aldehydes which do not have ................... undergo disproportionation reaction (or) cannizaro reaction.
Answer» SOLUTION : `ALPHA`- HYDROGEN ATOM

84831.	ADP and ATP differ in the numberof
Answer» phosphateunits ribose , units adenine BASE nitrogen atom. Solution :ADP is adenoisediphosphate and it has twophosphate GROUP while ATP is adenoisetriposphate and it has THREE phosphate group. THUS , ATP and ADP differ in NUMBEROF phosphate units.

84832.	Aldehydes usually do not form stable hydrates but chloral normally exists as chloral hydrate. Give reason.
Answer» Solution :In case of aldehyde REACTION is reversible. . In case of `C C I_(3)CHO,CI` atoms INCREASES +ve charge on CARBONYL carbon. Therefore ,weak nucleophiles LIKE WATER readily added to the carbonyl group. .

84833.	Aldehydes undergo disproportionation reaction in presence of aqueous NaOH. Simultaneou oxidation and reduction of a compound is scientifically called as disproportionation. Aldehydes having no alpha-hydrogen show this rection called Cannizzaro's reaction. Few exception are also there to this represented as : C_(6)H_(5)CHO+C_(6)H_(5)CHO overset(NaOH)underset(Delta)to C_(6)H_(5)COONa+C_(6)H_(5)CH_(2)OH Intramolecular Cannizzaro's reaction is also possible. Answer the following questions : Mixture of C_(6)H_(5)CHO and HCHO is treated with NaOH then Cannizzaro's reaction involves:
Answer» oxidation of HCHO reduction of HCHO oxidation of `C_(6)H_(5)CHO` reduction of `C_(6)H_(5)CHO` Answer :D

84834.	Adolfvon Beeyersuggestedthat,sincecarbonprefers tohavetetradralgeometrv wih bondanglesof approximately109^(@)ring sizesotherthanfiveand six may betoostrainedto exist ,Baeyer based hishypothesison thesimplegeometricalnationthata three-memberedring ( cyclopropane ) shouldbe anequilatera trianglewithbond anglesto 60^(@) a fourmembered ring (cyclobutane) shouldbe asquarewithbondanglesof 90^(@) and so on . Accordingto Beayer'sanalysiscyclopropane, witha bondablecompressionof 109^(@)-60^(@)=49^(@) , shouldhavea large amountof anglestrainand mustthereforebehighlyreactive cyclohexane becomes puckeredtoreeveitsstrainthe angulardeviation ofcycloalkaneis (-11^(@)) , Greater is the angulardeviationmore is thetorsinalstrain . whichamongthe followingis moststrainedcyclobalkane ?
Answer» CYCLOPROPANE CYCLOBUTANE CYCLOPENTANE cyclohexane Answer :A

84835.	Aldehydes undergo disproportionation reaction in presence of aqueous NaOH. Simultaneou oxidation and reduction of a compound is scientifically called as disproportionation. Aldehydes having no alpha-hydrogen show this rection called Cannizzaro's reaction. Few exception are also there to this represented as : C_(6)H_(5)CHO+C_(6)H_(5)CHO overset(NaOH)underset(Delta)to C_(6)H_(5)COONa+C_(6)H_(5)CH_(2)OH Intramolecular Cannizzaro's reaction is also possible. Answer the following questions : The aldehyde having alpha- hydrogen which gives Cannizzaro's reaction is :
Answer» `CH_(3)-CH_(2)-CHO` `CH_(3)-underset(CH_(3))CH-CHO` `CH_(3)-underset(CL)CH-CHO` `C_(2)H_(5)-CH_(2)-CHO` ANSWER :B

84836.	Adolfvon Beeyersuggestedthat,sincecarbonprefers tohavetetradralgeometrv wih bondanglesof approximately109^(@)ring sizesotherthanfiveand six may betoostrainedto exist ,Baeyer based hishypothesison thesimplegeometricalnationthata three-memberedring ( cyclopropane ) shouldbe anequilatera trianglewithbond anglesto 60^(@) a fourmembered ring (cyclobutane) shouldbe asquarewithbondanglesof 90^(@) and so on . Accordingto Beayer'sanalysiscyclopropane, witha bondablecompressionof 109^(@)-60^(@)=49^(@) , shouldhavea large amountof anglestrainand mustthereforebehighlyreactive cyclohexane becomes puckeredtoreeveitsstrainthe angulardeviation ofcycloalkaneis (-11^(@)) , Greater is the angulardeviationmore is thetorsinalstrain . whichof thefollowingis mostreactivecycloalkane ?
Answer» CYCLOPROPANE CYCLOBUTANE CYCLOPENTANE cyclohexane Answer :A

84837.	Aldehydes undergo disproportionation reaction in presence of aqueous NaOH. Simultaneou oxidation and reduction of a compound is scientifically called as disproportionation. Aldehydes having no alpha-hydrogen show this rection called Cannizzaro's reaction. Few exception are also there to this represented as : C_(6)H_(5)CHO+C_(6)H_(5)CHO overset(NaOH)underset(Delta)to C_(6)H_(5)COONa+C_(6)H_(5)CH_(2)OH Intramolecular Cannizzaro's reaction is also possible. Answer the following questions : The aldehyde which shows Cannizzaro's reaction is :
Answer» HCHO `C_(6)H_(5)CHO` `CCl_(3)-CHO` All of the above Answer :D

84838.	Adolf von Baeyer suggested that, since carbon prefers to have tetrahedral geometry with bond angles of approximately 109^@, ring sizes other than five and six may be too strained to exist. Baeyer based his hypothesis on the simple geometrical notion that a three-membered ring (cyclopropane) should be an equilateral triangle with bond angles to 60^@, a four membered ring (cyclobutane) should be a square with bond angles of 90^@ and so on. According to Baeyer's analysis, cyclopropane, with a bond angle compression of 109^@ - 60^@ = 49^@, should have a large amount of angle strain and must therefore be highly reactive. Cyclohexane becomes puckered to releave its strain. The angular derivation of cycloalkane is (-11^@). Greater is the angular deviation more is the torsional strain. Which among the following is most strained cycloalkane?
Answer» Cyclopropane Cyclobutane Cyclopentene Cyclohexane Answer :A

84839.	Aldehydes that do not undergo aldol condensation are (1) Propanal (2) Trichloroethanal (3) Methanal (4) Ethanal (5) Benzaldehyde
Answer» 3 and 4 only 3 and 5 only 1,2 and 3 only 2 and 5 only Solution :The carbonyl compound must contain an `alpha`-hydrogen atom, for it to undergo ALDOL condensation. However, formaldehyde, though CONTAINS no `alpha`-hydrogen atom yet undergoes abnormal aldol condensation in presence of LIME water.

84840.	Adolf von Baeyer suggested that, since carbon prefers to have tetrahedral geometry with bond angles of approximately 109^@, ring sizes other than five and six may be too strained to exist. Baeyer based his hypothesis on the simple geometrical notion that a three-membered ring (cyclopropane) should be an equilateral triangle with bond angles to 60^@, a four membered ring (cyclobutane) should be a square with bond angles of 90^@ and so on. According to Baeyer's analysis, cyclopropane, with a bond angle compression of 109^@ - 60^@ = 49^@, should have a large amount of angle strain and must therefore be highly reactive. Cyclohexane becomes puckered to releave its strain. The angular derivation of cycloalkane is (-11^@). Greater is the angular deviation more is the torsional strain. The tendency of cyclopropane (I), cyclopropane (II) and cyclopropane (III) to form addition compounds is in the order
Answer» `I GT II gt III` `I = II gt III` `I gt II = III` `I = III gt II` ANSWER :A

84841.	Aldehydes that do not undergo aldol condensation are
Answer» Propanal trichloroethanal methanal Ethanal. Answer :D

84842.	Adolf von Baeyer suggested that, since carbon prefers to have tetrahedral geometry with bond angles of approximately 109^@, ring sizes other than five and six may be too strained to exist. Baeyer based his hypothesis on the simple geometrical notion that a three-membered ring (cyclopropane) should be an equilateral triangle with bond angles to 60^@, a four membered ring (cyclobutane) should be a square with bond angles of 90^@ and so on. According to Baeyer's analysis, cyclopropane, with a bond angle compression of 109^@ - 60^@ = 49^@, should have a large amount of angle strain and must therefore be highly reactive. Cyclohexane becomes puckered to releave its strain. The angular derivation of cycloalkane is (-11^@). Greater is the angular deviation more is the torsional strain. Which among the following has greatest bond angle?
Answer» Cyclopropane Cyclobutane Cyclopentene Cyclohexane Answer :D

84843.	Aldehydes that do not undergo aldol condensation are (1) propanal (2) trichloroethanal(3) 2- phenylethanal(4) ethanal (5) benzaldehyde
Answer» 3 and 4 only 2 and 5 only 1, 2 and 3 only 2, 3 and 5 only Solution :The carbonyl COMPOUND must contain an `alpha`-HYDROGEN atom, for it to UNDERGO ALDOL condensation.

84844.	Aldehydes resemble ketones in many respects. What is Cannizzaro reaction?
Answer» ANSWER :REFER to THEORY

84845.	Adolf von Baeyer suggested that, since carbon prefers to have tetrahedral geometry with bond angles of approximately 109^@, ring sizes other than five and six may be too strained to exist. Baeyer based his hypothesis on the simple geometrical notion that a three-membered ring (cyclopropane) should be an equilateral triangle with bond angles to 60^@, a four membered ring (cyclobutane) should be a square with bond angles of 90^@ and so on. According to Baeyer's analysis, cyclopropane, with a bond angle compression of 109^@ - 60^@ = 49^@, should have a large amount of angle strain and must therefore be highly reactive. Cyclohexane becomes puckered to releave its strain. The angular derivation of cycloalkane is (-11^@). Greater is the angular deviation more is the torsional strain. Which of the following is most reactive cycloalkane?
Answer» Cyclopropane Cyclobutane Cyclopentene Cyclohexane Answer :A

84846.	Aditi, a class XII student, was discussing diazonium salts. She pointed out the diazonium salts couple with phenols/ amines to form azo dyes which are widely used to colour both the fabric and the food. The emphasized that although azo dyes are excellent for dyeing fabric but the food coloured with azo dyes is harmful particularly for young children and asthama patients. therefore, she stressed that only natural dyes should be used for colouring food. After reading the above passage, answer the following questions, (i) What are azo dyes ? Give one example. (ii) Name an azo dye which has been used as a food colour in the past but has now been benned?
Answer» Solution :(i) Dyes containing -N=N-as the functional group are called azo dyes. For example, the simplest azo dye is aniline yellow obtained by coupling benzenediazonium chloride with aniline. (II) An example of SYNTHETIC azo dye which has been USED to colour FOOD is tetrazine. it is CONSIDERED to be a cancer suspect.

84847.	Write a test to distinguish between aldehydes and ketones.
Answer» Answer :Tollen's reagent test and FEHLING's solution test (REFER THEORY)

84848.	Adipic acid underset(H^+)overset(2EtOH)to P overset(EtOH)to Q underset(2Br(CH_2)_3 CO_2. Et)overset(1. EtO)to R ,R is
Answer» `EtO_2 C - (CH_2)_4-CO_2 ET` `EtO_2 C-(CH_2)_4-CO_2 H` SOLUTION :

84849.	Aldehydes resemble ketones in many respects. Give the reason for their resemblance.
Answer» Answer :Both ALDEHYDES and ketones CONTAIN the carbonyl group C=O. So they RESEMBLE in many PROPERTIES.

84850.	Adm 'scatalyst is :
Answer» platinummetal PALLADIUM nickel METAL `PtO_(2)` Answer :D

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