$$CH_3CH (OH)_2, CH_3CH(OH)COOH$$

Assertion is correct but Reason is incorrect

Both Assertion and Reason are correct and Reason is the correct explanation for Assertion

Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion

Both Assertion and Reason are incorrect

Both Assertion and Reason are correct and Reason is the correct explanation for Assertion

Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion

Assertion is correct but Reason is incorrect

Both Assertion and Reason are incorrect

MCQ Questions for Class 12 Engineering Chemistry Aldehydes,Ketones And Carboxylic Acids Quiz 9

Among the following acids which has the lowest

$pKa$ value

0%
$CH_3COOH$
0%
$HCOOH$
0%
$(CH_3)_2CH-COOH$
0%
$CH_3CH_2COOH$

Explanation

$K_a\propto\frac{1}{pK_a};$ The value of

$K_a$ is highest for HCOOH .

Compounds

$(A)$ and

$(B)$ are:

The IUPAC name for the above compound is

0%
1-hydroxypentane-1,4-dione
0%
1, 4-dioxopentanol
0%
1-carboxybutan-3-one
0%
4-oxopentanoic acid

The general formula for aldehydes is

$C_nH_{2n+1}CHO$ . The value of n for the first member.

0%
$1$
0%
$0$
0%
$0.5$
0%
$1.1$

Explanation

The general formula of alkyl group is

$C_nH_{2n+1}CHO$ and hence general formula for aldehyde will be

$C_nH_{2n+1}CHO$ provided

$n = 0, 1, 2, 3,$ etc.

thus, the value of n for the first member is 0 i.e

$HCHO$

An organic compound X has the molecular formula

$C_3H_6O_2$ . It has a pleasant smell but does not turn blue litmus red. It has a structural formula.

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0%
0%
both (a) and (b)
0%
None of the above

Explanation

an organic compound that has the molecular formula

$C_3H_6O_2$ and having pleasant smell but does not turn blue litmus red suggests that it must be an ester.

thus, the structural formula is..... ( refers image)

1724835_1822446_ans_24f1ed4db76b4cdc83b5ab1558964c9e.jpg

The hybridization of carbonyl carbon in carbonyl compounds is

0%
$sp^2d$
0%
$sp^3$
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$sp^2$
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$sp$

The correct structure representation of carboxylate ion is

Explanation

The correct structural representation of carboxylate ion is

$RCOO^-$

Hence, Option "A" is the correct answer.

The IUPAC name for the formula

$CH_{3} - \overset{CH_{3}} {\overset{|} {C}} = \overset{H} {\overset{|} {C}} - COOH$

0%
$2$ -Methyl- $2$ -butenoic acid
0%
$3$ -Methyl- $3$ -butenoic acid
0%
$3$ -Methyl- $2$ -butenoic acid
0%
$2$ -Methyl- $3$ -butenoic acid

Fill in the blanks by suitable choices .
The carbon atom in carbonyl group is________ hybridised .The carbonyl group in aldehydes and ketones undergoes_______ reactions . Aldehydes which have

$\alpha - H$ atom undergo______ reaction .

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$sp^{3}$ , nucleophilic substitutions , aldol condensation , Cannizzaro
0%
sp , electrophilic substitution , Cannizzaro , aldol condensation .
0%
$sp^{2}$ , nucleophilic addition , aldol condensation Cannizzaro
0%
$sp^{3}$ electrophilic addition , Cannizzaro , aldol condensation .

Explanation

The carbon atom in carbonyl group is

$sp^{2}$ hybridised .The carbonyl group in aldehydes and ketones undergoes nucleophilic addition reactions . Aldehydes which have

$\alpha - H$ atom undergo aldol condensation reaction .

Hence, Option "C" is the correct answer.

$CH_3 - \underset{O}{\underset{||}{C}} - OH \xrightarrow[]{NaH{\overset{14}{C}O_3}} (P \,gas) \xrightarrow[(2) H_3O^{\oplus}]{(1)PhCH_2MgBr} (Q)$

$CH_{ 3 }-\overset { O }{ \overset { || }{ \underset { O }{ \underset { || }{ S } } } } -OH\xrightarrow [ ]{ NaH{ \overset { 14 }{ C } O_{ 3 } } } (R\, gas)\xrightarrow [ (2)H_{ 3 }O^{ \oplus } ]{ (1)Ph{ \overset { 14 }{ C } }H_{ 2 }MgBr } (S)$
Product (Q) and (S) in the aove reactions are respectively:

0%
$PhCH_2COOH, Ph - \overset{14}{C}H_2 - \overset{O}{\overset{||}{\underset{O}{\underset{||}{S}}}} - OH$
0%
$PhCH_2\overset{14}{C}OOH, Ph \overset{14}{C}H_2COOH$
0%
$PhCH_2\overset{14}{C}OOH, Ph\overset{14}{C}H_2 \overset{14}{C}OOH$
0%
$PhCH_2COOH, Ph\overset{14}{C}H_2 \overset{14}{C}OOH$

Explanation

$CH_3 - \underset{O}{\underset{||}{C}} - OH \xrightarrow[]{NaH\overset{14}{C}O_3} CH_3CO\overset{-}{O} \overset{+}{N}a + H_2O + \overset{14}{C}O_2$

$\overset{14}{C}O_2 \xrightarrow[(2) H_3O^{\oplus}]{(1) PhCH_2MgBr} \underset{(Q)}{PhCH_2\overset{14}{C}OOH}$

$CH_3 - \overset{O}{\overset{||}{\underset{O}{\underset{||}{S}}}} - OH \xrightarrow[]{NaH\overset{14}{C}O_3} CH_3SO_3Na + H_2O + \overset{14}{C}O_2$

$\overset{14}{C}O_2 \xrightarrow[(2) H_3O^{\oplus}]{(1) Ph\overset{14}{C}H_2MgBr} \underset{(S)} {Ph\overset{14}{C}H_2 \overset{14}{C}OOH.}$

Option C.

The structure of the product

$S$ is

By the action of malonic acid in ethanolic ammonia on benzaldehyde in the presence of pyridine, it forms:

0%
Benzoic acid
0%
Phenyl acetic acid
0%
Cinnamic acid
0%
Phthalic acid

In the following reaction sequence
What is X.

Which carbonyl group is protonated most readily in acidic solution, but gives nucleophilic addition by

$NH_{2}NH-Ph$ least readily?

The following conversion reaction can be carried out by using reaction sequence/s.

0%
0%
0%
0%
$KMnO_4 / OH^{\circleddash } / Heat$

The correct statement is

0%
If $(x)$ is $PhCH = O$ , then $(z)$ is also $PhCH = O$
0%
If $(x)$ is $PhCH = O$ , then $(y)$ is $Ph - CH = CH - CH = CH - COOH$
0%
0%
$x$ can be $CH_3 - CH = O$

0%
$CH_3CH (OH)_2, CH_3CH(OH)COOH$
0%
$CH_3CHO, CH_3CH(OH)COOH$
0%
$CH_3CH_2COOH, CH_3CH_2OH$
0%
$CH_3CH(OH)COOH, CH_3CH_2OH$

0%
Both Assertion and Reason are correct and Reason is the correct explanation for Assertion
0%
Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion
0%
Assertion is correct but Reason is incorrect
0%
Both Assertion and Reason are incorrect

Explanation

As, the functional group is

$-COOH$ , the numbering is done from RHS to give minimum number to carbon atom bearing the functional group. Rewriting the above structure. The chain consists of four carbon atoms. Hence its a derivative of butane.

The substituent is the methyl group. So the above compound is

$3-$ methyl butanoic acid.

In which of the following reactions correct major product is mentioned?

Which of the following products is/are correctly mentioned in the following reaction.

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$HCHO \xrightarrow[]{NaOD} HCOONa + CH_3OD$
0%
$HCDO \xrightarrow[]{NaOD} DCOONa + CH_2DOH$
0%
$HCDO \xrightarrow[]{NaOD} DCOOEt + DCH_3ONa$
0%
$D_2CO \xrightarrow[]{NaOD} DCOONa + CD_3OD$

Which of the following is a mixed ketone

0%
Pentanone
0%
Acetophenone
0%
Benzophenone
0%
Butanone

Explanation

$\text{Mixed ketones are the complex ketones in which both the groups are not same. i.e one is alkyl and another is}$

$\text{aromatic.}$

Acetophenone | ≥99%(HPLC) | Selleck | Others chemical

Thus, the correct answer is B.

What is the correct

$IUPAC$ name for

0%
5-methyl-3-hexenoic acid
0%
5-carboxy-2-methylpentene
0%
4-isotropyl-3-butenoic acid
0%
None of these

The

$IUPAC$ name for

$\begin{matrix} { CH }_{ 3 }CH={ CH }{ CH }_{ 2 }{ CH }{ CH }_{ 2 }COOH \\ \quad \quad| \\ \quad \quad{ CH }_{ 2 } \end{matrix}$ is

0%
$5-$ aminohex $-2-$ ene carboxylic acid
0%
$5-$ amino $-2-$ heptenoic acid
0%
$3-$ amino $-5-$ heptenoic acid
0%
$\beta -$ amini $-\delta -$ heptenoic acid

Explanation

$\begin{matrix} \overset { 7 }{ { CH }_{ 3 } } & - & \overset { 6 }{ CH } & = & \overset { 5 }{ CH } & - & \overset { 4 }{ { CH }_{ 2 } } & - & \overset { 3 }{ CH } & - & \overset { 2 }{ { CH }_{ 2 } } & - & \overset { 1 }{ COOH } \\ & & & & & & & & | & & & & \\ & & & & & & & & { NH }_{ 2 } & & & & \end{matrix}$

$3-$ amino

$-5-$ heptenoice acid

What is the compound called if remaining two valencies of a carbonyl group are satisfied by two alkyl groups

0%
Aldehyde
0%
Ketone
0%
Acid
0%
Acid chloride

Explanation

The compound formed is known as

$Ketone.$ And according to question, the compound so formed has a structure,

$R_2C=O.$ And this is the general structure of ketones.

Addition of alcohols to aldehydes in presence of anhydrous acid yield

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Carboxylic acids
0%
Ethers
0%
Cyclic ethers
0%
Acetals

Addition of alcohols to aldehydes in presence of anhydrous acid yield:

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Carboxylic acids
0%
Ethers
0%
Cyclic ethers
0%
Acetals

Explanation

Alcohols are added to aldehydes and ketones in the presence of dry hydrogen chloride to form hemiacetals. This reaction can continue by adding another alcohol to form an acetal.

Hence, option

$D$ is correct.

1644028_1763780_ans_add2daf1ef0a4e3db72738f59196dabf.png

Compound

$(A)$ is:

Carboxylic acid

$(A)$ is:

0%
0%
0%
0%
Both (a) and (c)

Explanation

Formation of

$(E)$ suggests monosubstituted acid and reaction of 1 mol of

${H}_{2}$ with (A) and (B) shows one

$(C=C)$ bond. There are 6 D.U (4 D.U for

$(Ph)$ group, 1 D.U for

$(COOH)$ and 1 D.U for

$(C=C)$ in both (A) and (B)

Chiral compound with nine

$C$ atoms would be (given figure)

Here

$(C)$ and

$(D)$ can be distinguished quantitatively by H.V.Z reaction.

$(C)$ has one

$\alpha$ - H atoms and would give dichlorinated product. The chlorine content in the chlorinated derivaties of

$(C)$ and

$(D)$ is determined by quantitative methods

1774741_1767788_ans_095eef2ada444fcabcaa824e8f8b6e3e.PNG

${CH}_{3}CH=CHCHO$ is oxidised to

${CH}_{3}CH=CHCOOH$ using:

0%
Alkaline $KMn{O}_{4}$
0%
Selenium dioxide
0%
Ammoniacal $Ag{NO}_{3}$
0%
All

Explanation

Since alkaline

$KMnO_4$ are powerful oxidizing agents, they can oxidize double bond also, to protect double bond, we use a mild oxidizing agent as

$Tollen's\ [Ag(NH_3)_2]+OH−$ oxidizes

$CHO$ to

$COOH$ without affecting the

$(C=C)$ bond. and

$Ag(0)$ (mirror) is precipitated.
1777309_1768382_ans_5da4edd36a324a559e587b6651ab80aa.png

Which of the following statements are correct?

0%
Oximes are stronger acids than hydroxylamine
0%
$p{K}_{a}$ of maleic acid is less than $p{K}_{a}$ of fumaric acid
0%
${Me}_{3}Si{CH}_{2}COOH$ is a stronger acid than ${Me}_{3}C-{CH}_{2}COOH$
0%
o-Nitrobenzoic acid is a weaker acid than 3,5-dinitrobenzoic acid

Select the correct order in sequence in order to get the final product (E).

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$(X)\, (U) \, (Z) \, (W) \, (U/X),(Y)$
0%
$(X) \,(U) \,(Z) \,(V) \,(U/X),(Y)$
0%
$(X) \,(Z) \,(W) \, (U/X),(Y) \,(V)$
0%
$(X) \,(Z) \,(W) \,(U) \,(V)$

Five isomeric p-substituted aromatic compounds (A) to (E) with molecular formula

$C_8H_8O_2$ are given for identification. Based on the following observation, give the structures of the compounds.
i. Both (A) and (B) form a silver mirror with Tollens reagent. (B) also gives a positive test with neutral

$FeCl_3$ solution.
ii. (C) gives positive iodoform test.
iii. (D) is readily extracted in aqueous

$NaHCO_3$ solution.
iv. (E) on acid hydrolysis gives 1,4 - dihydroxy benzene.
Compound (D) is:

0%
Both Assertion and Reason are correct and Reason is the correct explanation for Assertion
0%
Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion
0%
Assertion is correct but Reason is incorrect
0%
Both Assertion and Reason are incorrect

Explanation

Since 3-phenol propanoic acid is

${1}^{o}RX$ , preparation by both methods can occur.

Option A is correct.

1778774_1768422_ans_575bb3c9ae7f4a49b33beb8c20b83d19.jpg

Which of the following reactions are correct?

Which of the following is the correct repeseentaation for intermediate of nucleophilic addition reaction to the given carbonyl compound (A):

Aldehyde and ketones do not react with

0%
Sodium bisulphide
0%
Phenylhydrazine
0%
Dihydrogen sodium phosphate
0%
Semicarbazide

Which of the following reagent are not correctly matched with the reaction ?

0%
$CH_{3}CH = CHCHO \rightarrow CH_{3}CH = CHCOOH :$ Ammonical $AgNO_{3}$
0%
$CH_{3}CH = CHCHO \rightarrow CH_{3}CH =CHCH_{2}OH : H_{2}/Pt$
0%
$R - COOH \rightarrow R - CH_{2}OH : NaBH_{4}$
0%
$CH_{3}CH_{2}COCl \rightarrow CH_{3}CH_{2}CHO : H_{2}CH_{2}CHO : H_{2}, PD /NASO_{4}$

Explanation

The incorrect reaction from the given reactions is reaction"B"

Corrected Reaction:

$\mathrm{CH_{3}CH = CHCHO \overset{H_{2}/{Pt}}{\rightarrow} CH_{3}CH_{2}CH_{2}CH_{2}OH}$

Hence, Option "B" is the correct answer.

Match column I with column II and mark the appropriate choice.

0%
$(A) \rightarrow (i) , (B) \rightarrow (ii) , (C) \rightarrow (iii) , (D) \rightarrow (iv)$
0%
$(A) \rightarrow (iv) , (B) \rightarrow (iii) , (C) \rightarrow (ii) , (D) \rightarrow (i)$
0%
$(A) \rightarrow (ii) , (B) \rightarrow (iv) , (C) \rightarrow (iii) , (D) \rightarrow (i)$
0%
$(A) \rightarrow (iii) , (B) \rightarrow (i) , (C) \rightarrow (ii) , (D) \rightarrow (iv)$

Explanation

Hint: Aldehydes and ketones can undergo both oxidation and reduction reduction.

Step 1: Oxidation and reduction reaction of aldehydes and ketones.

Carbonyl compounds are the ones that consist of a carbonyl group ( $-C=O$ ) in their structure. Aldehydes and ketones are examples of carbonyl compounds. Carbonyl compounds like aldehydes and ketones can undergo oxidation reactions to form carboxylic acid and sodium salt of carboxylic acid. Also, it can undergo reduction reactions to form alkanes and alcohols.

Step 2: Given oxidation and reduction reactions of aldehydes and ketones.

Aldehyde and ketones undergo reduction reactions in the presence of reducing agent $LiAlH_4$ to form alcohols. In this, the carbonyl group $-C=O$ gets converted into $-CH_2OH$ . Aldehyde and ketones can also be reduced to alkanes in the presence of Zn/HCl and conc. HCl. During this reaction, $-C=O$ group gets converted into $-CH_2$ group.

Oxidation reaction of aldehyde and ketones in the presence of $Ag_2O/OH^-$ leads to the formation of carboxylic acid. In this oxidation reaction, $-C=O$ group is converted into $-COOH$ . Similarly, the oxidation of aldehyde and ketones can also occur in the presence of NaOX but the product formed in this reaction is sodium salt of carboxylic acid. The carbonyl group $-C=O$ in this reaction is changed into $-COONa$ .

Final step:

Hence, the option B is correct.

2116788_1847166_ans_feb7e12e5f4e465c9ee8baa055b54d09.JPG

$\alpha$ - Hydroxypropanoic acid can be prepared from ethanal by following the steps given in the sequence .

0%
Treat with HCN followed by acidic hydrolysis
0%
Treat with $NaHSO_{3}$ followed by reaction with $Na_{2}CO_{3}$
0%
Treat with $H_{2}SO{4}$ followed by hydrolysis
0%
Treat with $K_{2}Cr_{2}O_{7}$ in presence of sulphurilic acid .

Explanation

Reaction for obtaining

$\mathrm{\alpha}$ -Hydroxypropanoic acid from ethanal is:

$\mathrm{\underset{Ethanal}{H_3C-CHO} + HCN \xrightarrow{\ \ \ \ } H_3C-C(OH)-CN \xrightarrow{H_3O^+} \underset{\alpha- Hydroxy \ Propnoic \ Acid}{H_3C-CH(OH)-COOH}}$

Hence, Option "A" is the correct answer.

Identity reactant (X) in the given reaction sequence .

$\mathrm{CH_{3}COCH_{3} + X \rightarrow (CH_{3}) _3C - (OMgCl) \overset{H_{2}O}{\rightarrow} (CH_3)_3C-OH}$

0%
$CH_{3}Mg Cl$
0%
$CH_{3}COCl + Mg$
0%
$Mg Cl_{2}$
0%
$CH_{3} CH_{2} MGCl$

Explanation

Complete Reaction:

$\mathrm{ CH_{3}COCH_{3} + CH_3MgCl \rightarrow (CH_{3}) _3C - (OMgCl) \overset{H_{2}O}{\rightarrow} (CH_3)_3C-OH}$

So, X is

$\mathrm{CH_3MgX}$

Hence, Option "A" is the correct answer.

Study the following sequence of reaction and identify the product (Y).

$CH_{3} CHO + HCHO \xrightarrow[heat]{dil . NaOH} X \xrightarrow[H_{3}O^{+}]{HCN} Y$

The end product (Z) in the given sequence of reaction is

$CH_{3}CH = CHCHO \overset{NaBH_{4}}{\rightarrow} X \xrightarrow[ZnCl_{2}]{HCl} Y \xrightarrow[(ii)H^{+}]{KCN} Z$

0%
$CH_{3}CH = CHCH_{2}COOH$
0%
$CH_{3}CH_{2}CH_{2}COOH$
0%
$CH_{3}CH = CHCOOH$
0%
$CH_{3}CH (Cl)CH_{2}COOH$

Explanation

Complete Reaction:

$CH_{3}CH = CHCHO \overset{NaBH_{4}}{\rightarrow} CH_3CH-CH_2CH_2OH \xrightarrow[ZnCl_{2}]{HCl} CH_3CH=CHCH_2Cl \xrightarrow[(ii)H^{+}]{KCN} CH_3CH=CHCH_2COOH$

So, the end product Z is

$CH_{3}CH = CHCH_{2}COOH$

Hence, Option "A" is the correct answer.

A compound (X) having molecular formula

$C_{4}H_{8}O_{2}$ is hydrolysed by water in presence of an acid to give a carboxylic acid (Y) and an alcohol (Z) . (Z) on oxidation with chrome acid gives (Y), (X), (Y) and (Z) are

0%
X $CH_{3}COOCH_{3}$
Y $CH_{3}COOH$
Z $CH_{3}OH$
0%
X $CH_{3}COOC_{2}H_{5}$
Y $CH_{3}COOH$
Z $C_{2}H_{5}OH$
0%
X $C_{2}C_{5}COOCH_{3}$
Y $C_{2}C_{5}COOH$
Z $C_{2}H_{5}OH$
0%
X $CH_{3}COOC_{2}H_{5}$
Y $C_{2}H_{5}COOH$
Z $CH_{3}OH$

Explanation

As the compound on hydrolysis gives carboxylic acid, so, the given compound X is a ketone.

Ketones possible with molecular mass

$\mathrm{(C_4H_8O_2)}$ are

$\mathrm{CH_3-COO-C_2H_5}$ and

$\mathrm{C_2H_5-COO-CH_3}$

X is

$\mathrm{CH_3-COO_C_2H_5 \ or \ C_2H_5-COO-CH_3 }$

Y is

$\mathrm{CH_3COOH \ or \ C_2H_5COOH}$

Z is

$\mathrm{CH_3-CH_2OH \ or \ C_2H_5-CH_2OH}$

Hence, Option "B" is the correct answer.

Which functional group does

$CH_{3}COCH_{3}$ contains ?

0%
$-CHO$
0%
$-\overset {\overset {\displaystyle {\text O}}{||}} C-$
0%
$-COOH$
0%
$-OH$

Product

$A$ and

$B$ for the following reactions are as follows:

0%
0%
0%
0%
None of the above

The IUPAC name of

$CH_{3}CH = CHCOOC_{2}H_{5}$ is

0%
Ethyl but-1-enoate
0%
Ethyl but-2-enoate
0%
Ethyl prop-2-enoate
0%
None of these

Cyclohexanone

$\xrightarrow{Cl_2/NaOH}$

$A$

$\xrightarrow{i)NaOH/H_2O}$

$B$

The product B and type of reaction occurs in conversion of A to B respectively are:

0%
Cyclohexanecarboxylic acid, Beckmann Rearrangement
0%
Benzoic acid, Wolf Rearrangement
0%
Cyclopentanecarboxylic acid, Favorskii Rearrangement
0%
Cyclohexanecarboxylic acid, Curtius Rearrangement

$CH_{3}OH \xrightarrow[(ii)\: Rh, \: \Delta]{(i)\: X} CH_{3}COOH$
In the above reaction,

$X$ is :

0%
$CO_{2}$
0%
$CO$
0%
$MgO$
0%
$C$

Explanation

The compound

$X$ is

$CO$ .
The reaction is as follows:

$CH_{3}OH \xrightarrow[(ii)\: Rh, \: \Delta]{(i)\:{CO}} CH_{3}COOH$
The reaction of

$CO$ with methanol, followed by heating with

$Rh$ gives acetic acid. This process is called as Monsanto process.

The compound(B) in the below reaction is:

$C_{2}H_{5}Cl\overset{KCN}{\rightarrow}A\overset{H_{3}O^{+}}{\rightarrow}B$

0%
ethylene chloride
0%
acetic acid
0%
propionic acid
0%
ethyl cyanide

Explanation

$C_{2}H_{5}Cl\overset{KCN}{\rightarrow}\underset {A}{C_{2}H_{5}-C \equiv N} \overset{H_{3}O^{+}}{\rightarrow}\underset {B}{C_{2}H_{5}-COOH}$

In the first reaction, cyanide ion substitutes chloride ion.

In the second reaction, acid hydrolysis converts the cyanide group to the carboxylic group.

The compound (B) in the below reaction is propionic acid.

Option C is correct.

CBSE Questions for Class 12 Engineering Chemistry Aldehydes,Ketones And Carboxylic Acids Quiz 9 - MCQExams.com

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Practice Class 12 Engineering Chemistry Quiz Questions and Answers

CBSE Questions for Class 12 Engineering Chemistry Aldehydes,Ketones And Carboxylic Acids Quiz 9 - MCQExams.com

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Practice Class 12 Engineering Chemistry Quiz Questions and Answers

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