Chemistry · Science General

Alcohols, Ethers and Carboxylic Acids

391 Questions

Alcohols, ethers, and carboxylic acids questions explore organic chemistry reactions, chemical formulas, and compound identifications. The topics cover practical applications like antifreeze production and specific chemical conversions. This material helps candidates preparing for science oriented competitive exams.

Organic reactionsChemical compounds identificationAlcohol conversionCarboxylic acid propertiesIndustrial chemical applications

Alcohols, Ethers and Carboxylic Acids Questions

Multiple choice chemistry chemical kinetics kinetic study of some first order reactions rate of chemical reaction endothermic and exothermic reactions

The hydrolysis of ethyl acetate in an acidic medium is a:

  1. zero order reaction

  2. first order reaction

  3. pseudo first order reaction

  4. second order reaction
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation
$1.$ Decomposition of $H _2O _2$ in aqueous solution.
$H _2O _2\rightarrow H _2O+1/2O _2$
$2.$ Hydrolysis of methyl acetate in the presence of mineral acids.
$CH _3COOCH _3 +H _2O\rightarrow CH _3COOH+CH _3OH$
$3.$ Inversion of cane sugar in the presence of mineral acids.
$C _{12}H _{22}O _{11}+H _2O\xrightarrow {[H^+]}C _6H _{12}O _6+C _6H _{12}O _6$
$4.$ Decomposition of ammonium nitrate in aqueous solution.
$NH _4NO _2\rightarrow N _2+2H _2O$
$5.$ Hydrolysis of diazo derivatives.
$C _5H _5N+NCl + H _2O\rightarrow C _6H _5OH+N _2+HCl$
FIRST ORDER REACTION : When the rate of reaction depends only on one concentration term of reactant. A first order reaction is one whose rate varies as first power of the concentration of the reactant, i.e. the rate increases as number of times as the concentration of reactant is increased.
Examples are given above:
Multiple choice chemistry chemical kinetics kinetic study of some first order reactions rate of chemical reaction endothermic and exothermic reactions

The hydrolysis of ethyl acetate,
$CH _{3}COOC _{2}H _{5} + H _{2}O\xrightarrow {H^{+}} CH _{3}COOH + C _{2}H _{5}OH$ is a reaction of:

  1. zero order

  2. pseudo first order

  3. second order

  4. third order
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

A reaction which is not the first-order reaction naturally but made the first order by increasing or decreasing the concentration of one or the other reactant is known as Pseudo first-order reaction. 


Hydrolysis of ethyl acetate in presence of an excess of water:

$CH _3COOC _2H _5+H _2O(\text{excess}) \xrightarrow{H+} CH _3COOH+C _2H _5OH$

$r = k[CH _3COOC _2H _5]^2[H _2O]^0$

Excess $[H _2O]$ can cause the independency of reaction on $H _2O$.


Hence, it is a pseudo-first-order reaction.

Hence, the correct answer is option $\text{B}$.

Multiple choice chemistry hard water and soft water heavy water study of heavy water hydrogen and its compounds

Which of the following is not the possible enol form of propanone in the presence of heavy water?

  1. ${ CH } _{ 3 }-CD=\overset { \overset { OD }{ | } }{ C } -D$
  2. ${ CH } _{ 3 }-\overset { \overset { OD }{ | } }{ C= } CHD$
  3. ${ CH } _{ 2 }=\overset { \overset { OD }{ | } }{ C- } { CD } _{ 3 }$
  4. ${ CD } _{ 2 }=\overset { \overset { OD }{ | } }{ C- } { CD } _{ 3 }$
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

In the presence of D2O, the alpha-hydrogens of propanone are replaced by deuterium through keto-enol tautomerism. Option A shows a structure that is not a standard enol form of propanone as it implies incorrect substitution patterns or connectivity for the enolization of propanone.

Multiple choice biology coal, petroleum and petrochemicals carbon cycling mineral coal carbon cycle coal and its products

What chemical reaction makes biodiesel?

  1. transesterification

  2. sublimation

  3. polymerization

  4. fermentation
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation
Sublimation is the transition of a substance directly from the solid to the gas phase, without passing through the intermediate liquid phase.

Polymerization is a process of reacting monomer molecules together in a chemical reaction to form polymer chains.

The chemical breakdown of a substance by bacteria, yeasts, or other microorganisms, typically involving effervescence and the giving off of heat is called fermentation.

Transesterification is the process of exchanging the organic group R″ of an ester with the organic group R′ of an alcohol.
The alcohol reacts with the fatty acids to form the mono-alkyl ester (biodiesel) and crude glycerol.

Biodiesel production is the process of producing the biofuel, biodiesel, through the chemical reactions transesterification and esterification. This involves vegetable or animal fats and oils being reacted with short-chain alcohols (typically methanol or ethanol).
Multiple choice chemistry petrochemicals and polymers petroleum properties of alkanes petroleum and natural gas rocks and minerals

Which of the following is used as an anti -knocking compound?

  1. TEL
  2. $C _2H _5OH$

  3. Glyoxal

  4. Freon
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

An anti-knocking agent is the substance which is used to reduce the engine knocking. It increases the octane number of the fuel. It helps in auto-ignition by raising the temperature and pressure. TEL is tetraethyl Lead which is used as an Anti-Knocking compound.

Multiple choice biology human health and disease drug, tobacco and alcohol consumption addiction and dependence community health and hygiene

In the liver, alcohol is converted into which toxic substance?

  1. Formic acid

  2. Acetaldehyde

  3. Nicotine

  4. Urea
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

There are 2 ways that alcohol can be processed by your liver. Most alcohol is broken down, or metabolised, by an enzyme in your liver cells known as alcohol dehydrogenase (ADH). ADH breaks down alcohol into acetaldehyde and then another enzyme, aldehyde dehydrogenase (ALDH), rapidly breaks down acetaldehyde into acetate. The acetate is further metabolised and eventually leaves your body as carbon dioxide and water.

Acetaldehyde is a toxic substance that can cause an unpleasant reaction when it builds up. Symptoms you might experience if your ALDH enzyme does not function properly include flushing of the face, hot sensations, nausea and palpitations (an awareness of your heart beating faster than normal).
Therefore, the correct answer is option B.

Multiple choice biology human health and disease drug, tobacco and alcohol consumption addiction and dependence community health and hygiene

In liver, alcohol is converted into a more toxic substance called

  1. Acetaldehyde

  2. Formaldehyde

  3. Hydrogen cyanide

  4. Methane
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation
In liver, alcohol is converted to acetaldehyde by the enzyme alcoholic dehydrogenase. Acetaldehyde is more toxic than alcohol and its accumulation can cause hangover symptoms in which unpleasant mental and physical experiences occur in body. It can alter various functions of liver by binding to different proteins. Formation of adduct of acetaldehyde affects activity of various enzymes. It may also cause dizziness and skin reactions too.
So, the correct answer is 'Acetaldehyde'.
Multiple choice commercial applications bioenergy biofuels making biofuels technological and industrial development

Gasohol contains

  1. $50-60\%$ alcohol
  2. $10-15\%$ alcohol
  3. $30-40\%$ alcohol
  4. $80-90\%$ alcohol
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation
Gasohol is a mixture of gasoline and alcohol (generally the composition of mixture is 9:1 for gasoline and alcohol i.e. 90% gasoline and 10% alcohol. It is used as fuel in engines. In many countries, gasohol is used as an alternative fuel in engines. The advantage of using gasohol is that there is less emission of pollutants because gasohol burns slowly and completely. However, alcohol based gasohol is expensive so it is not commonly used.
So, the correct answer is '10- 15% alcohol'.
Multiple choice chemistry energy rocks and minerals petroleum and natural gas fossil fuels

Which of the following can be used to increase the octane number?

  1. Increasing the percentage of branched or cycloalkanes

  2. By addition of BTX or TEL

  3. By addition of powder alcohol (ethanol)

  4. All of the above.
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Octane number can be increased by any of the following methods:
(1) Increasing the percentage of branched or cycloalkanes.
(2) By addition of BTX or TEL.
(3) By addition of powder alcohol (ethanol).

Multiple choice chemistry chemical kinetics dependence of reaction rate on concentration of reactants order of reactions factors influencing rate of a reaction

The rate of solvolysis of tert-butyl bromide will be maximum in which of the following solvents?

  1. ${ Et } _{ 2 }O$
  2. ${CCl} _{4}$
  3. $EtOH$
  4. ${H} _{2}O$
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

The rate of solvolysis of Tert - butyl bromide will be maximum in Water.

tert-butyl bromide follows $SN1$ mechanism thus it prefers weak nucleophiles like water.

Multiple choice chemistry chemical kinetics dependence of reaction rate on concentration of reactants order of reactions factors influencing rate of a reaction

The following data were obtained for the saponification of ethyl acetate using equal concentrations of ester and alkali. The reaction order is:

Time(min) 0 4 10 20
Vol. of acid(mL)  8.04 5.30 3.50 2.22

  1. 0

  2. 1

  3. 2

  4. 3
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Saponification of ethyl acetate with equal concentrations of ester and alkali is a classic second-order reaction. The data provided would show a linear relationship for 1/[concentration] vs time, confirming second-order kinetics.

Multiple choice chemistry chemistry in daily life antimicrobials and antifertility drugs therapeutic action of different classes of drugs drugs and their classification

What is tincture of iodine?

  1. 2-3% solution of iodine in alcohol-water mixture.

  2. A mixture of iodine in chloroxylenol.

  3. A mixture of 0.2% phenol and 2-3% iodine in water.

  4. 2-3% solution of iodine in potassium iodide.
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

2-3% solution of iodine in alcohol-water mixture is known as tincture of iodine. It is a powerful antiseptic.