UPSEE: Important Questions & Short notes for Aldehydes, Ketones and Carboxylic Acids

Uttar Pradesh State Entrance Examination (UPSEE) is a state level engineering entrance examination for degree level engineering institutions and other professional colleges. It is regulated by Dr. A.P.J. Abdul Kalam Technical University (AKTU) formerly known as Uttar Pradesh Technical University (UPTU).

The chapter “Aldehydes, Ketones and Carboxylic Acids” is very important part of Organic Chemistry in the syllabus of UPSEE/UPTU 2018. Students always get about 2-3 questions from different topics like physical properties, chemical properties, name reactions of this chapter in the examination.

UPSEE/UPTU Chemistry Syllabus: 2017 - 2018

Students should try to understand the mechanism of all the reactions in Organic Chemistry instead of rote learning.

In this article, Subject Experts bring to you the short notes including previous years’ solved questions for the examination.

Students can study the following topics here:

1. Preparation of Aldehyde

2. Physical properties of Aldehyde

3. Chemical Properties of Aldehyde

4. Preparation of Ketone

5. Physical properties of Ketone

6. Chemical Properties of Ketone

7. Preparation of Carboxylic Acid

8. Physical properties of Carboxylic Acid

9. Chemical Properties of Carboxylic Acid

10. Name reactions like Rosenmund reduction, Stephen reaction, Etard reaction, Gatterman - Koch reaction, Friedel-Crafts acylation, Canninzzaro reaction

About the notes:

• These chapter notes are based on the latest syllabus of the examination.
• These notes are prepared by Subject Experts of Chemistry after the detailed analysis of last few year papers of UPSEE/UPTU entrance examination.
• With the help of these notes aspirants will get complete overview of the chapter.

Important Concepts:

Physical Properties of Aldehyde:

• The first two members of aldehyde are gases.
• Next eight members (C₃ - C₁₁) of aldehyde are liquids and the higher aldehydes are solid
• The boiling points of Aldehydes, Ketones and Carboxylic Acids are higher than hydrocarbons and ethers of comparable molecular masses.
• The lower members of aldehydes are miscible with water in all proportions.
• The lower aldehydes have sharp pungent odours.
• As the size of the molecule increases, the odour becomes less pungent and more fragrant.

UPSEE: Important Questions and Study notes for Hydrocarbons

Aldol condensation:

• Aldol means aldehyde and alcohol group on the same molecule.
• Reaction is only possible between two components having α - hydrogen.
• The reaction mechanism involves the formation of enolate ion and nucleophilic attack at a carbonyl carbon.
• Looses water in the presence of an acid forming α - β - unsaturated aldehyde or ketone.

Cannizzaro reaction:

• The reaction uses an aldehyde with no hydrogen atom on α - carbon.
• Due to deficiency of α - hydrogen aldol reaction is not possible.
• Hydroxide ion attack one of the carbonyls forming a tetrahedral intermediate.
• Reforming of pi bond lakes place.

Some previous years’ solved questions are given below:

Question 1:

The IUPAC name for

(a) 5-amino-2-heptenoic acid

(b) 5-amino hex-2-ene-carboxylic acid

(c) 3-amino-5-heptenoic acid

(d) P-amino-6-heptenoic acid

Solution 1:

So, the IUPAC name for the given compound is 3-amino-5-heptenoic acid.

Hence, the correct option is (c).

Question 2:

The following compound can exhibit

(a) geometrical isomerism

(b) geometrical and optical isomerism

(c) optical isomerism

(d) tautomerism

Solution 2:

Hence, geometrical isomers are not possible.

Hence, the correct option is (c).

Question 3:

IUPAC name of the following is :

(a) 2,5 Butyl butenal

(b) 2,3 di ethyl butenal

(c) 2 ethyl-3 methyl pentanal

(d) 8 methyl—2 ethyl pentanal

Solution 3:

The IUPAC name for the given compound is 2 ethyl-3 methyl pentanal.

Hence, the correct option is (c).

Question 4:

What is the name of the following reaction?

(a) Hell-Volhard reaction

(b) Clemmensen reaction

(c) Cannizzaro reaction

(d) None of the options

Solution 4:

The above reaction is Cannizzaro reaction.

Hence, the correct option is (c).

Question 5:

What is the product in the following reaction?

(a) Benzoic Acid

(b) Benzoquionone

(c) Cyclohexane-1-one

(d) Benzoic sulphate

Solution 5:

Hence, the correct option is (b).

Question 6:

In aldol addition reaction product is always:

(a) β - hydroxyaldehyde

(b) β - hydroxyketone

(c) α, β - unsaturated aldehyde

(d) α, β - unsaturated ketone

Solution 6:

In aldol addition it is β hydroxyl aldehyde(aldol both alcohol and aldehyde group) But in aldolcondensation the product is α, β - unsaturated aldehyde.

Hence, the correct option is (c).

Question 7:

Which of the following represents the correct order of the acidity in the given compound?

(a) CICH₂COOH < BrCH₂COOH < CH₃COOH < FCH₂COOH

(b) CH₃COOH < BrCH₂COOH < CICH₂COOH < FCH₂COOH

(c) FCH₂COOH < CICH₂COOH < BrCH₂COOH < CH₃COOH

(d) CH₃COOH < FCH₂COOH < CICH₂COOH < BrCH₂COOH

Solution 7:

The acidity of halogenated acid increases almost proportionately with the increase in electronegativity of the halogen present.

So, the correct order of the acidity in the given compound is

CH₃COOH < BrCH₂COOH < CICH₂COOH < FCH₂COOH

Question 8:

Aldol condensation reaction is not given by

(a) C₆H₅CH₂CHO

(b) C₆H₅CHO

(c) CH₃CHO

(d) CH₃COCH₃

Solution 8:

C₆H₅CHO has no H and α-carbon.

Thus, no aldol condensation reaction is given by C₆H₅CHO.

Hence, the correct option is (b).

Conclusion:

These notes will help you to understand all concepts related to chapter Aldehydes, Ketones and Carboxylic Acids in an easiest possible way. With the help of these notes students can easily understand the mechanisms of all important name reactions related to this chapter.

Ozonolysis: Alkene Reactions

Mathematics all chapters complete notes for UPSEE/UPTU 2018