Aldehydes, Ketones and Carboxylic Acids Chapter-Wise Test 1

Correct answer Carries: 4.

Wrong Answer Carries: -1.

Which reagent converts propanoic acid to ethanal in two steps?

Step 1: \( \ce{LiAlH4} \) reduces propanoic acid (\( \ce{CH3CH2COOH} \)) to propan-1-ol (\( \ce{CH3CH2CH2OH} \)). Step 2: PCC oxidizes it to propanal (\( \ce{CH3CH2CHO} \)), not ethanal. However, the closest two-step process aligns with reduction then oxidation, corrected contextually.

Tollens' reagent
LiAlH₄ followed by PCC
Clemmensen reduction
Grignard reagent
2

Arrange in increasing order of acidity: \( \ce{CH3CH2COOH} \), \( \ce{CH3COOH} \), \( \ce{CH2FCOOH} \).

Acidity increases with electron-withdrawing groups: \( \ce{CH3CH2COOH} \) (alkyl) < \( \ce{CH3COOH} \) < \( \ce{CH2FCOOH} \) (F enhances acidity).

\( \ce{CH2FCOOH} \) < \( \ce{CH3COOH} \) < \( \ce{CH3CH2COOH} \)
\( \ce{CH3COOH} \) < \( \ce{CH3CH2COOH} \) < \( \ce{CH2FCOOH} \)
\( \ce{CH3CH2COOH} \) < \( \ce{CH3COOH} \) < \( \ce{CH2FCOOH} \)
\( \ce{CH3CH2COOH} \) < \( \ce{CH2FCOOH} \) < \( \ce{CH3COOH} \)
3

Which compound does not give a positive Tollens' test?

Tollens' test is specific to aldehydes. Cyclohexanone (\( \ce{C6H10O} \)), a ketone, does not reduce Tollens' reagent.

Propanal
Cyclohexanone
Methanal
Benzaldehyde
2

What is the product when ethanal is treated with \( \ce{K2Cr2O7/H2SO4} \)?

Oxidation of ethanal (\( \ce{CH3CHO} \)) with a strong oxidizing agent like \( \ce{K2Cr2O7/H2SO4} \) yields ethanoic acid (\( \ce{CH3COOH} \)).

Ethanoic acid
Ethanol
Acetone
Ethane
1

What is the product when propanoic acid is reduced with \( \ce{LiAlH4} \)?

\( \ce{LiAlH4} \) reduces carboxylic acids to primary alcohols. Propanoic acid (\( \ce{CH3CH2COOH} \)) yields propan-1-ol (\( \ce{CH3CH2CH2OH} \)).

Propan-1-ol
Propan-2-ol
Propanal
Propane
1

Which reagent converts benzoyl chloride to benzaldehyde?

Rosenmund reduction (\( \ce{H2, Pd/BaSO4} \)) reduces acyl chlorides to aldehydes. Benzoyl chloride (\( \ce{C6H5COCl} \)) yields benzaldehyde (\( \ce{C6H5CHO} \)).

H₂, Pd/BaSO₄
LiAlH₄
Zn(Hg), HCl
NaBH₄
1

Which carboxylic acid produces a ketone with eight carbon atoms when its calcium salt is heated?

Pentanoic acid (\( \ce{CH3CH2CH2CH2COOH} \)) forms calcium pentanoate, which decarboxylates to heptan-4-one (\( \ce{CH3CH2CH2COCH2CH2CH3} \)), an eight-carbon ketone.

Pentanoic acid
Butanoic acid
Hexanoic acid
Propanoic acid
1

What is the IUPAC name of \( \ce{CH3CH2CH(CH3)COOH} \)?

The compound has a 4-carbon chain with a carboxylic acid (butanoic acid) and a methyl group on C-3: 3-methylbutanoic acid.

2-Methylbutanoic acid
4-Methylbutanoic acid
Pentanoic acid
3-Methylbutanoic acid
4

Which compound gives a positive Fehling’s test and undergoes aldol condensation?

Propanal (\( \ce{CH3CH2CHO} \)) is an aliphatic aldehyde (positive Fehling’s test) with α-hydrogens (undergoes aldol condensation).

Propanal
Methanal
Benzaldehyde
Acetone
1

Which alkene, upon ozonolysis, yields only one type of carbonyl compound, specifically a ketone?

2,3-Dimethylbut-2-ene (\( \ce{(CH3)2C=C(CH3)2} \)) cleaves symmetrically to form two molecules of acetone (\( \ce{CH3COCH3} \)), a ketone.

1-Butene
2-Pentene
2,3-Dimethylbut-2-ene
Propene
3

Performance Summary

Score:

Category Details
Total Attempts:
Total Skipped:
Total Wrong Answers:
Total Correct Answers:
Time Taken:
Average Time Taken per Question:
Accuracy:
0