ECAT Pre Engineering Chemistry Chapter 23 MCQ Test With Answer

Which alcohol may be oxidised to a product which react with 2,4-dinitorphenylhydrazine reagent but not with Fehling's reagent

• Butan-1-ol A
• Butan-2-ol B
• 2-methylpropan-1-ol C
• 2-methylpropan-2-ol D

Which compound on reaction with hydrogen cyanide produces a compound with a chiral centre

• Ch₃CHO A
• CH₃CH₂COCH₂CH₃ B
• CH₃CO₂CH₃ C
• HCHO D

A common industrial solvent is a mixture of propanone; CH₃COCH₃, and pentyl ethanoate CH₃CO₂(CH₂)₄CH₃. Which reagent would have no effect on this solvent

• Na_(s) A
• NaBH₄ B
• NaOH_(aq) C
• 2,4-dinitrophenylhydrazine reagent D

Common names of aldehydes are given by corresponding:

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

Ketons are prepared by the oxidation of

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

Tollen's reagent is

• Ammonical cuprous chloride A
• Ammonical cuprous oxide B
• Ammonical silver bromide C
• Ammonical silver nitrate D

Formula of acetone is:

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

At room temperature formaldehyde is

• Gas A
• Liquid B
• Solid C
• None of the above 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

• Treatment with HCN followed by acid hydrolysis A
• Oxidation of acetaldehyde followed by basic hydrolysis B
• Treatment with HCN followed by reduction C
• Treatment with HCN followed by oxidation D

From which of the following tertiary butyl alcohol is obtained by the action of methyl magnesium iodide?

• HCHO A
• CH₃CHO B
• CH₃COCH₃ C
• CO₂ D

Aldehydes which do not haveα-hydrogen undergo

• Aldol combination A
• Cannizzaro's reaction B
• Substitution C
• Elimination 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

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

Ketones are prepared by the oxidation of:

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

Which of the following gives iodoform on heating with a solution of I₂containing Na₂CO₃?

• Ethyl alcohol A
• Acetone B
• Ethyl alcohol as well as acetone C
• Methyl alcohol D

In which reaction, aromatic aldehyde is treated with acid anhydride in the presence of corresponding salt of the acid to give unsaturated aromatic acid?

• Friedel-Crafts reaction A
• Perkin's reaction B
• Wurtz reaction C
• None of these D

Acetaldehyde is used to make

• Rubbber A
• Antiseptics B
• Phenolic resin C
• All of these D

Which of the following compounds will react with Tollen's reagent

• 
  A
• 
  B
• 
  C
• 
  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

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

Aldelydes are the oxidation product of

• P-alcohols A
• s-alcohols B
• ter-alcohols C
• carboxylic acids D

Chromic acid used to oxidize

• Aldehyde A
• Ketone B
• Both a and b C
• None of these D

Iodoform test is given by:

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

Which of the following is a method of converting a unsaturated ketone into unsaturated hydrocarbon?

• Aldol condensation A
• Reimer Tiemann reaction B
• Cannizaaor's reaction C
• Wolf-kishner reduction D

The addition of HCN to carbonyl compounds is an example of

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

The color of ppts formed by Fehling's test is

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

Which of the following is halo form

• CHBr₃ A
• CHCI₃ B
• CHI₃ C
• All of these D

Cannizzzaro's reaction is not given by:

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