Condensation Reactions Flashcards
- Condensation reaction is the reverse of which of the
following reaction?
a) lock and key hypothesis
b) oxidation
c) hydrolysis
d) glycogen formation
c) hydrolysis
- Condensation reaction always results in the formation
of complex sugar (disaccharide or polysaccharide) and
which of the following?
a) amino acids
b) lipids
c) water
d) maltose
c) water
- In which condensation an enol or an enolate ion reacts
with a carbonyl compound to form a β-hydroxyaldehyde
or β-hydroxyketone (an aldol reaction), followed by
dehydration to give a conjugated enone happens?
a) Aldol condensation
b) Claisen reduction
c) Henry condensation
d) Knoevenagel condensation
a) Aldol condensation
- Which of the following statements is wrong?
a) The base-catalysed α-halogenation of propanone is first order in the concentration of the base
b) The rate constant for the base-catalysed α-halogenation
of propanone decreases in the order Cl2 > Br2 > I2
c) The base-catalysed α-halogenation of propanone
proceeds easily to give 1,1,1-trihalopropanone
d) Polyhalogenation of propanone is difficult under acidic
conditions, but the products are the same as those
obtained under basic conditions
b) The rate constant for the base-catalysed α-halogenation
of propanone decreases in the order Cl2 > Br2 > I2
- Which of the following statements is wrong?
a) Hydrolysis of an acetal is catalysed by acids
b) Hydrolysis of an acetal is catalysed by aqueous acid
c) Oximes are stabilized by conjugation between the C=N
and OH groups
d) Enamines are formed between secondary amines and
the carbonyl group of aldehydes and ketones
b) Hydrolysis of an acetal is catalysed by aqueous acid
- Acetal on acid hydrolysis generates which of the
following?
a) Alcohol
b) Amine and aldehyde
c) Ketone and alcohol
d) Ketone and ether
c) Ketone and alcohol
- Dimethoxymethane is dimethyl acetal of which of the
following?
a) Formaldehyde
b) Acetaldehyde
c) Tolualdehyde
d) Propionaldehyde
a) Formaldehyde
- Which of the following is not polyacetal?
a) Dimethoxymethane
b) Dioxolane
c) Starch
d) Cellulose
d) Cellulose
- In keto-enol from presence of which type of hydrogen is
must?
a) Alpha
b) Beta
c) Gamma
d) Any position of hydrogen
a) Alpha
- Which of the following tautomeric form is more stable?
CH3-CH=O ↔ CH2=C-OH
(I) (II)
a) I
b) II
c) Both are equally stable
d) Both are unstable
a) I
- Hydrolysis of CH3CH2NO2 with 85% H2SO4 gives which of
the following compound?
a) CH3CH2OH
b) C2H6
c) CH3CH=NOH
d) CH3COOH
d) CH3COOH
- Acetic acid is obtained when which of the given reaction
takes place?
a) Methyl alcohol is oxidised with potassium
permanganate
b) Calcium acetate is distilled in the presence of calcium
formate
c) Acetaldehyde is oxidised with potassium dichromate
and sulphuric acid
d) Glycerol is heated with sulphuric acid
c) Acetaldehyde is oxidised with potassium dichromate
and sulphuric acid
- Acetic acid is manufactured by the fermentation of
which of the following reaction?
a) Ethanol
b) Methanol
c) Ethanal
d) Methanal
a) Ethanol
- When benzyl alcohol is oxidised with KMnO4, the
product obtained is which of the following compound?
a) Benzaldehyde
b) Benzoic acid
c) CO2 and H2O
d) Benzophenone
a) Benzaldehyde
- Which of the following gives benzoic acid on oxidation?
a) Chlorophenol
b) Chlorotoluene
c) Chlorobenzene
d) Benzyl chloride
d) Benzyl chloride
- Formic acid is obtained when which of the given
reaction occurs?
a) Calcium acetate is heated with conc. H2SO4
b) Calcium formate is heated with calcium acetate
c) Glycerol is heated with oxalic acid at 110℃
d) Acetaldehyde is oxidised with K2Cr2O7 and H2SO4
c) Glycerol is heated with oxalic acid at 110℃
- o-xylene when oxidised in presence of V2O5 the product
is which carboxylic acid?
a) Benzoic acid
b) Phenyl acetic acid
c) Phthalic acid
d) Acetic acid
c) Phthalic acid
- By aerial oxidation, which one of the following gives
phthalic acid?
a) Naphthalene
b) Benzene
c) Mesitylene
d) Toluene
a) Naphthalene
- Which of the following acids has the smallest
dissociation constant?
a) CH3CHFCOOH
b) FCH2CH2COOH
c) BrCH2CH2COOH
d) CH3CHBrCOOH
c) BrCH2CH2COOH
- The vapour of a carboxylic acid HA when passed over
MnO2 at 573 K yields propanone. What is the acid HA?
a) Methanoic acid
b) Ethanoic acid
c) Propanoic acid
d) Butanoic acid
b) Ethanoic acid
- Which acid is strongest or Which is most acidic?
a) Cl2CH.COOH
b) ClCH2COOH
c) CH3COOH
d) Cl3C.COOH
b) ClCH2COOH
- The acid which reduces Fehling solution is which of the
following?
a) Methanoic acid
b) Ethanoic acid
c) Butanoic acid
d) Propanoic acid
a) Methanoic acid
- Which class of compounds shows H-bonding even more
than in alcohols?
a) Phenols
b) Carboxylic acids
c) Ethers
d) Aldehydes
b) Carboxylic acids
- Which of the following is the strongest acid?
a) CH3COOH
b) BrCH2COOH
c) ClCH2COOH
d) FCH2COOH
d) FCH2COOH
- The reaction of HCOOH with conc.H2SO4 gives which of
the following compound?
a) CO2
b) CO
c) Oxalic acid
d) Acetic acid
b) CO
- Which one is strongest acid among following options?
a) CH2FCOOH
b) CH2ClCOOH
c) CHCl2COOH
d) CHF2COOH
b) CH2ClCOOH
- Acetic acid is weak acid than sulphuric acid because
which of the following reasons?
a) It decomposes on increasing temperature
b) It has less degree of ionisation
c) It has -COOH group
d) It has more inductive effect
b) It has less degree of ionisation
- In CH3COOH and HCOOH, HCOOH will be which of the
following?
a) Less acidic
b) Equally acidic
c) More acidic
d) cannot say about acidic behaviour
c) More acidic
- Hydrogenation of C6H5CHOH−COOH over
Rh−Al2O3catalyst in methanol gives which of the following?
a) C6H5CH2COOH
b) C6H11CHOHCOOH
c) C6H5CHOHCH2OH
d) C6H11CH2COOH
b) C6H11CHOHCOOH
- In the anion HCOO− the two carbon-oxygen bonds are
found to be of equal length. What is the reason for it?
a) Electronic orbitals of carbon atom are hybridised
b) The C = O bond is weaker than the C – O bond
c) The anion HCOO− has two resonating structures
d) The anion is obtained by removal of a proton form the
acid molecule
b) The C = O bond is weaker than the C – O bond
- Carboxylic acids are more acidic than phenol and alcohol
because of which of the following?
a) Intermolecular hydrogen bonding
b) Formation of dimers
c) Highly acidic hydrogen
d) Resonance stabilization of their conjugate base
d) Resonance stabilization of their conjugate base
- When propionic acid is treated with aqueous sodium
bicarbonate CO2 is liberated. The ‘C’ of CO2 comes from
which of the following?
a) Methyl group
b) Carboxylic acid group
c) Methylene group
d) Bicarbonate
d) Bicarbonate
- The compound not soluble in acetic acid is which of the
following?
a) CaCO3
b) CaO
c) CaC2O4
d) Ca(OH)2
c) CaC2O4