ECAT Pre Engineering Chemistry Chapter 23 MCQ Test With Answer

Chromyl chloride and toluene react to produce

• p-chlorotoluene A
• Benzaldehyde B
• Benzyl chloride C
• Bezoic acid D

Propyne on hydrolysis in presence of H₂SO₄and HgSO₄gives

• Acetaldehyde A
• Acetone B
• Formaldehyde C
• None D

Common names of aldehydes are given by corresponding:

• Ketone A
• Alcohol B
• Carboxylic acid C
• ester D

Aldehyde and small methyl ketones form crystalline ______ ppts with saturated sodium bisulphate solution

• White A
• Red B
• Yellow C
• None of these 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

A food chemist wants to create the odour of pineapples for a product. An ester with this odour has the formula C₃H₇COOC₂H_5.Which pair of reagents would produce this ester

• C₂H₅CI and C₃H₇COOH A
• C₂H₅OH and C₃H₇CONH₂ B
• C₂H₅OH and C₃H₇COOH C
• C₃H₇OH and C₂H₅COCI D

Ethanal may be converted into a three-carbon acid in a two-step process.

Which compound is the intermediate

• CH₃CO₂H A
• CH₃CN B
• CH₃CH₂CN C
• CH₃CH(OH)CN 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

A compound R has all of the following properties. It is neutral; It gives an orange precipitate with 2,4-dinitrophenythydrazine; it evolves hydrogen chloride when treated with PCI₅in the cold What could R be

• 
  A
• 
  B
• 
  C
• 
  D

Which of the following compounds gives a ketone with Grignard's reagent?

• Formaldehyde A
• Ethanenitrile B
• Ethyl alcohol C
• Methyl iodide 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

On adding sodium nitroprusside ketones give

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

Ketones are prepared by the oxidation of:

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

Which of the following compounds does not react with NaHSO₃?

• C₆H₅CHO A
• Acetophenone B
• Acetone C
• Acetaldehyde D

Cannizzaro reaction is not given by

• Trimethyl acetaldehyde A
• Acetaldehyde B
• Benzaldehyde C
• Formaldehyde D

Which of the following is hypnotic?

• Acetaldehyde A
• Metaldehyde B
• Paraldehyde C
• None D

Which is not true about acetophenone?

• Reacts to form 2,4-dintrophenyl hydrazine A
• Reacts with Tollen's reagent to form silver mirror B
• Reacts with I₂/NaOH to form iodoform C
• On oxidation with alkaline KMnO₄followed by hydrolysis gives benzoic acid D

Which one of the following statement is wrong regarding differences between aldehydes and ketones

• Aldehydes undergo reduction to form primary alcohols while ketones undergo reduction to form secondary alcohols A
• Aldehydes undergo oxidation to form acids having less number of carbon atoms while ketones undergo oxidation to form acids having same number of carbon atoms B
• Aldehydes give positive silver mirror test while ketones give negative -mirror test C
• Aldehydes can undergo polymerization while ketones cannot undergo polymerizarion D

• 2-chlorobutanal A
• alfa-chlorobutanal B
• 2-chlorobutyraldehyde C
• alfa- chlorobutyraldehyde D

Isopropyl alcohol on oxidation forms

• Acetone A
• Ether B
• Ethylene C
• Acetaldehyde D

Calcium acetate when dry distilled gives

• Formaldehyde A
• Acetaldehyde B
• Acetone C
• Acetic anhydride D

Which reagent could be used to distinguish between CH₃CH(OH)CH₂CHO and CH₃COCH₂CH₂OH

• Acidified potassium dichromate A
• Dilute sulphuric acid B
• 2,4-dinitrophenylydrazine C
• Fehling's reagent D

In carboxyl group the bond between C and oxygen is:

• Sigma bond A
• Single bond B
• Double Bond C
• Triple bond D

An organic compound 'A' has the molecular formula C₃H₆O, it undergoes iodoform test. When saturated with HCl it gives 'B' of molecular formula C₉H₁₄O. A and B, respectively are

• Propanal and mesitylene A
• Propanone and mesityl oxide B
• Propanone and 2, 6-dimethyl-2,5-heptadien-4-one C
• Propanone and mesitylene oxide D

What is formed when propanone is refluxed with an anhydrous solution of NaBH₄

• Propanal A
• Propan-1-ol B
• Propan-2-ol C
• Propane 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

Formalin is an aqueous solution of

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

Clemensen's reduction of ketones is carried out in

• H₂with Pd catalyst A
• Glycol with KOH B
• LiAIH₄in water C
• Zn-Hg with conc. HCl D