ECAT Pre Engineering Chemistry Chapter 23 MCQ Test With Answer

Which is used for the reduction of aldehydes and ketones

• NaBH₄ A
• Pt/Pd B
• Ni C
• All of these D

Ketones are prepared by the oxidation of

• Primary alcohol A
• Secondary alcohol B
• Tertiary alcohol C
• None of these D

An organic compound has the following properties ; It gives a positive tri-iodomethane test; it gives a yellow ppt, with 2, 4-DNP regent; it does not react with Tollen's reagent . Which compound would give these results

• CH₃CHO A
• CH₃CH₂OH B
• CH₃CH₂COCH₃ C
• CH₃CH₂CH₂CHO D

The product of the reaction between propanone and HCN is hydrolysed under acidic conditions. What is the formula of the final product

• CH₃CH(OH)COOH A
• CH₃CH₂CH(OH)COOH B
• (CH₃)₂C(OH)COOH C
• CH₃CH₂CH₂COOH D

Aldol condensation is actually

• Electrophilic addition of carbonation A
• Electrophilic addition of carbonium ion B
• Nucleophilic addition of carbonation C
• Nuclephilic addition of carbonium ion D

The homologous series of aldehydes and ketones have general formula:

• C_nH_2nO A
• C_nH_nO B
• C_nH_2n-1O C
• C_nH_nO_n D

The addition of HCN to carbonyl compounds is an example of

• Nucleopihlic substituion A
• Electrophilic addition B
• Nueleophilic addition C
• Electrophilic substitution D

Which of these reactions is shown by buranone, CH₃COCH₂CH₃

• On warming with acidified potassium dichromative (IV) the solution turns green A
• On heating with Fehling's reagent a red precipitate is formed B
• With 2,4-dinitrophenlhydrazine reagent an orange precipitate is formed C
• With hydrogen cyanide an aldehyde is formed D

The carbon atom of a carbonyl group is

• Sp hybridized A
• Sp²hybridized B
• Sp³hybridized C
• None of these D

Reduction of aldehydes with HI and P gives

• Primary alcohols A
• Secondary alcohols B
• Alkanes C
• Tertiary alcohols D

Formula of acetone is:

• HCHO A
• CH₃CHO B
• CH₃OCH₃ C
• CH₃OC₂H₅ D

Aromatic aldehydes undergo disproportionation in presence of sodium or potassium hydroxide to give corresponding alcohol and acid. The reaction is known as

• Wurtz reaction A
• Cannizzaro reaction B
• Friedel Craft reaction C
• Claisen reaction D

Which of the following reagents is used to distinguish acetone and acetophenone

• NaHSO₃ A
• Grinard reagent B
• Na₂SO₄ C
• NH₄Cl D

• 
  A
• 
  B
• 
  C
• 
  D

Acetone is oxidized with

• Tollen's reagent A
• Fehling solution B
• Acidic dichromate solution C
• Benedicts solution D

Formalin is an aqueous solution of

• Furfural A
• Fluorescein B
• Formaldehyde C
• Formic acid D

Acetone reacts with HCN to form a cyanohydrin. It is an example of

• Electrophilic addition A
• Electrophilic substitution B
• Nucleophilic addition C
• Nucleophilic substitution D

Acetone is prepared by

• Oxidation of n-propyl alcohol A
• Oxidation of acetaldehyde B
• Pyrolysis of calcium acetate C
• Pyrolysis of calcium acetate as well as acetic acid D

Carboxyl compounds have functional group:

• R-C-X A
• R-CH=O B
• RCOR C
• All D

Aledehydes ketones can be prepared form alcohols by their:

• Reduction A
• Oxidation B
• Decomposition C
• Synthesis D

Which reagent will distinguish a ketone from an aldehyde

• Br₂ A
• 2, 4-dinitrophenylhydrazine B
• NaBH₄ C
• Tollen's reagent D

The colour of ppts formed by Fehling's test is

• Brick red A
• Red B
• Yellow C
• Orange D

Reaction of Grignard's reagent with ketones gives: Reaction of Grignard's reagent with formaldehyde gives:

• Pri-alcohol A
• Sec-Alcohol B
• Ter-alcohol C
• Carboxylic D

In aldol condensation reaction, a double bond is formed between ______ and ______ carbon atoms

• αandβ A
• αandα B
• αand Y C
• None of these D

Which of the following react with NaOH to produce an acid and an alcohol?

• NCHO A
• CH₃COOH B
• CH₃CH₂COOH C
• C₆H₅COOH D

• Br_2(aq) A
• 2, 4-dinitrophenylhydrazine B
• NaBH C
• Tollen's reagent D

Formaline Contains ______% alcohol

• 80 A
• 37 B
• 8 C
• 52 D

Dehydration of allcohol gives:

• Alkane A
• Alkene B
• Aldehyde C
• ketone D

On adding sodium nitroprusside ketones give

• Red A
• Wine red B
• White C
• Orange D

Iodoform test is given by:

• Formaldehyde and Higher ketones A
• Formaldehyde B
• Acetaldehyde and methyl ketones C
• Acetaldehyde D