Alcohols Phenols and Ethers Test - 17

Tertiary butyl alcohol is obtained by the action of methyl magnesium bromide on acetone CH₃COCH₃.

Methyl magnesium bromide is CH₃MgX and falls in the category of Grignard Reagents. The methyl group bears a partial negative charge and the metal bears a partial positive charge. Ketones react with a Grignard reagent to give tertiary alcohols as addition products.

Aldehydes give secondary alcohol and formaldehyde gives primary alcohol. The reaction is a step-up reaction as the number of carbon atoms increases in the product.

The reaction of acetone with methyl magnesium halide is given as follows:

The product of the reaction is tertiary butyl alcohol.

Hence, the correct option is (C).

The process of benzoylation of compounds containing active hydrogen such as phenol, aniline, alcohol, etc, with benzoyl chloride in the presence of aqueous NaOH is called Schotten-Baumann reaction.

The reaction are as follows:

Hence, the correct option is (C).

Ethyl alcohol is denatured by adding methanol and pyridine.

Denatured alcohol, also called methylated spirits  or wood spirit or denatured rectified spirit, is ethanol  that has additives to make it poisonous, bad-tasting, foul-smelling, to discourage recreational consumption. It is sometimes dyed so that it can be identified visually. Pyridine, Methanol  or both can be added to make denatured alcohol poisonous, and denatonium can be added to make it bitter.

Hence, the correct option is (B).

In propanone((CH₃)₂CO), the functional group present is a ketone (- C=O) group.

Acetone also is known as Propanone is an organic compound with the formula (CH₃)₂CO.

In propanol (C₃H₇OH), the functional group present is an alcohol (- OH) group.

In propanoic acid (C₂H₅COOH), the functional group present is a carboxylic acid (- COOH) group. 

In ethanal (CH₃CHO), the functional group present is an aldehyde(- CHO) group.

In propanal (C₂H₅CHO), the functional group present is an aldehyde(- CHO) group.

Hence, the correct option is (A).

Glycerol is Trihydric alcohol.

Compounds having one −OH group is called monohydric alcohol.

Compounds having two −OH group is called dihydric alcohol.

Compounds having three −OH group is called trihydric alcohol.

Image of glycerol is given below, it has three −OH group.

Hence, the correct option is (D).

Phenols do not react with sodium bicarbonate.

Phenols are weakly acidic and bicarbonate ions are not strong enough to take the H⁺ from phenols. Phenols are weakly acidic in nature. They turn blue litmus red and react with alkali metals and alkalies to form their salts. Phenol is a weaker acid than carboxylic acid. Thus, it behaves differently from other acids in that it does not react with sodium bicarbonate.

Hence, the correct option is (A).

Stephen's reduction converts ethane nitrile into ethanal or Acetaldehyde.

When ethane nitrile is treated with Sn/HCl, it undergoes Stephen's reaction to form  Acetaldehyde.

The reaction is:

The reaction is more efficient when aromatic nitriles are used rather than aliphatic nitriles. The reaction is a redox reaction and electron-withdrawing substituents can improve the rate of the reaction.

Hence, the correct option is (B).

Tertiary butyl alcohol is most reactive with Lucas Reagent.

Ethanol is a primary alcohol and does not give instant turbidity with Lucas Reagent. Methanol is also primary alcohol that does not give turbidity with Lucas Reagent. Isopropyl alcohol is secondary alcohol that gives turbidity with Lucas Reagent after 5 to 10 minutes.

Tertiary butyl alcohol is tertiary alcohol that gives turbidity instantaneously on reaction with Lucas Reagent. The reaction can be given as follows:

Hence, the correct option is (D).

Structural formula of Haloalkane is R-X.

It was derived from alkanes containing a halogens or more.

They are used as flame retardants, fire extinguishers, refrigerants, propellants, solvents, and medicinal items.

"RX" in which R is an alkyl or alkyl substituted group and X is a halogen (F, Cl, Br, I).

Haloalkanes are commonly used in organic synthesis as synthonous alternatives to alkyl cation (R+).

Hence, the correct option is (D).

Phenol on hydrogenation with Ni at 433K gives cyclohexanol.

The hydrogenation reaction is the addition of hydrogen to compounds.

Raney Ni, which is a finely divided Nickel powder is used in the hydrogenation process because it adsorbs the hydrogen molecules and provides high catalytic efficiency.

When phenol is treated with Ni at 433K, it converts to Cyclohexanol.

It is a highly selective reaction.

The reaction of reduction of phenol is given as:

When phenol is reacted with zinc dust it forms benzene.

Zinc oxidized itself and become ZnO and reduces phenol to benzene.

Hence, the correct option is (C).

Soaps are sodium or potassium salts of long-chain of carboxylic acids.

Sodium salts of fatty acids are called hard soaps and potassium salts of fatty acids are called soft soaps.

Soaps are sodium or potassium salts of long-chain fatty acids.

Alcohol carries one hydroxyl functional group (at least) which is bound to a saturated carbon atom. The molecular formula is C_nH_2n+1OH.

Aldehydes carry a functional group with the structure − CHO. In this, a carbon atom shares a double bond with an oxygen atom, a single bond with a hydrogen atom, and a single bond with another atom. 

Esters are derived from carboxylic acids (-COOH group). The hydrogen is replaced by a hydrocarbon group in esters.

Hence, the correct option is (A).

Ethyl alcohol is industrially prepared from ethylene by Absorbing in H₂SO₄ followed by hydrolysis.

Acid-catalyzed hydration of Alkene:

Alkenes react with water (hydrolysis) in the presence of acid as a catalyst to form alcohols.

In the case of unsymmetrical alkenes, the addition reaction occurs in accordance with Markovnikov’s rule.

Mechanism:
Step 1: Protonation of an alkene to form carbocation by an electrophilic attack of hydronium ion (H₃O⁺).

Step 2: Nucleophilic attack of water on carbocation.

Step 3: Deprotonation to form an alcohol.

Industrial preparation of Ethyl alcohol:

• Ethanol reacts with sulphuric acid to form an intermediate product.
• This is followed by hydrolysis to give ethanol and H₂SO₄ as byproducts.
• Here, the H₂SO₄ formed as a byproduct is reused for further reaction with ethyl alcohol.

The reaction is as follows:

\(CH _{2}= CH _{2} \stackrel{ H _{2} SO _{4}}{\longrightarrow} CH _{3}- CH _{2}- HSO _{4} \stackrel{\text { Hydrolysis }}{\longrightarrow} CH _{3} CH _{2}- OH + H _{2} SO _{4}\)

Hence, the correct option is (C).

Phenol is also known as Carbolic acid. In 1865, the British surgeon Joseph Lister used phenol as an antiseptic to sterilize his operating field.

Phenol is an aromatic organic compound characterized by a hydroxyl (―OH) group attached to a carbon atom that is part of an aromatic ring.

Besides serving as the generic name for the entire family, the term phenol is also the specific name of its simplest member, monohydroxybenzene (C₆H₅OH).

Hence, the correct option is (B).

Ether (Diethyl ether) is an industrial solvent used for oils, fats, gum, resin, in perfumery, as a refrigerant, as a general anaesthetic etc.

Diethyl ether produces cooling on evaporation. So, it is a refrigerant. Diethyl ether was widely used as an anesthetic agent.

Thus, all the given options are correct.

Hence, the correct option is (D).

Functional group -CHO is present in Aldehydes.

Aldehyde is a class of organic compounds, in which a carbon atom shares a double bond with an oxygen atom, a single bond with a hydrogen atom, and a single bond with another atom or group of atoms (designated R in general chemical formulas and structure diagrams).

The double bond between carbon and oxygen is characteristic of all aldehydes and is known as the carbonyl group.

Aldehydes are often written in the short form as R–CHO

Aldehydes are considered the most important functional group.

Aldehydes contain the carbonyl group bonded to at least one hydrogen atom.

The IUPAC system of nomenclature assigns a characteristic suffix -al to aldehydes. For example, H2C=O is methanol.

The functional group of -OH is Alcohol.

The functional group of >C=O is Ketone.

The functional group of -COOH is Carboxylic acid.

Hence, the correct option is (B).

Formaldehyde is also known as formalin.

It is an organic compound which occurs naturally with formula CH₂O (H−CHO).

It is an effective precursor for many other chemicals and compounds.

This is primarily used in industrial resin processing, e.g. for particle boards and coatings.

Acetaldehyde and Acrolein are the Aldehydes while Acetone is the Ketones.

Hence, the correct option is (D).

All the given options are correctly matched.

Aldehyde has \(C _{n} H _{2} O\) general formula. Example: Ethanal \(- C _{2} H _{4} O , n =2\)

Carboxylic acid has \(C _{n} H _{2 n} O _{2}\) general formula. Example: Propionic acid \(- C _{3} H _{6} O _{2}, n =3\)

Cycloalkane has \(C _{ n } H _{2 n }\) general formula. Example: Cyclobutane \(- C _{4} H _{8}, n =4\)

Alkane also has \(C _{n} H _{2 n +2}\) general formula. Example: Ethane \(- C _{2} H _{6}, n =2\)

Hence, the correct option is (D).

Correctly match functional group given in List-I with the Nomenclature of that functional group given in list-II:

When a primary amine reacts with chloroform in alcoholic KOH, the product is an isocyanide.

Carbylamine reaction:

• Primary amines when treated with chloroform and ethanolic KOH gives carbylamines or isocyanides.
• The reaction occurs via carbene intermediate,
• Chloroform reacts with KOH to give chloro carbene: CCl2.

The general form of the reaction is:

For example,

Hence, the correct option is (A).

When Benzoyl chloride reacts with hydrogen in presence of palladium catalyst and barium sulphate, benzaldehyde is formed. This is known as Rosenmund reaction.

It is a reduction reaction where hydrogen is added to benzoyl chloride in presence of a catalyst. The catalyst is poisoned with sulfur or quinoline to prevent over reduction of the compound to alcohol.

The alcohol formed then may react with the benzoyl chloride to form esters, thus the presence of catalyst poison is very important.

The reaction can be given as follows:

Hence, the correct option is (B).

1−pentanol will be the least soluble in water.

Pentan-1-ol is an alkyl alcohol that is pentane in which a hydrogen of one of the methyl groups is substituted by a hydroxy group. Alcohols are soluble in water due to hydrogen bonding. However, as the length of carbon chain increases, the extent of hydrogen bonding decreases due to bulky chain.

According to this, 1−pentanol will be the least soluble in water, among the other given alcohols.

Hence, the correct option is (D).

Ethanol containing some methanol added to is called methylated spirit.

The methylated spirits contain ethyl alcohol mixed with other chemical substances including chemicals like methanol, methyl isobutyl ketone, and benzene, while the mineral turpentine contains a mixture of aliphatic, open-chain or alicyclic hydrocarbon compounds.

Hence, the correct option is (A).

Under ultra-violet light, three chlorine molecules add to benzene to produce benzene hexachloride, C₆H₆C_l6 which is also called gammaxane. Benzene hexachloride is an isomer of hexachlorocyclohexane with a chemical formula C₆H₆C_l6. It is also known as Lindane or hexachloride.

Uses of Benzene hexachloride (C₆H₆C_l6):

• Benzene hexachloride is used as an insecticide on crops, in forestry, for seed treatment.
• It is used in the treatment of head and body lice.
• It is used in pharmaceuticals.
• It is used to treat scabies.
• It is used in shampoo.

Hence, the correct option is (B).

By heating alkyl halide with sodium or potassium alkoxides (Williamson synthesis) diethyl ether is formed. This is the most important industrial and laboratory method and may be used for preparing simple as well as mixed ethers.

For example: \(C _{2} H _{5} ONa + C _{2} H _{5} I \rightarrow C _{2} H _{5} O \cdot C _{2} H _{5}+ NaI\)

Hence, the correct option is (B).

A functional isomer of Dimethyl ether is Ethanol.

It has the same chemical formula but different functional groups attached to them. e.g C₃H₆O

It has two functional isomers i.e.,

Hence, the correct option is (A).

Alpha hydroxy ketones and Aldehydes give a positive test with Tollens' reagent.

Ketones generally don’t give positive test with Tollen’s reagent, but alpha hydroxyl ketones are an exception. Iodoform test, Ester test, etc., are used for alcohols. The litmus test, Sodium bicarbonate test and Ester test are used for carboxylic acid.

Hence, the correct option is (D).

Formation of Ethanol:

\({ H _{2} C = CH _{2}}\) (Ethene) \(\underset{ H _{2} O }{\stackrel{ H _{2} SO _{4}}{\longrightarrow}} H _{3} C - CH _{2} OH\) (Ethanol)

\(\underset{\text { Glucose (Sugar) }}{ C _{6} H _{1} 2 O _{6}} \stackrel{\text { Zymase enzyme }}{\longrightarrow} \underset{\text { Ethanol }}{ C _{2} H _{5} OH }\)

So, Ethanol can be formed from Ethene and Fermentation of sugar.

Hence, the correct option is (C).

Carbon-dioxide and water both are produced when alcohol is added to petrol and used as a fuel.

For example, Ethanol is used as an additive in gasoline (Petrol) by some countries as its impact on the environment is much lower than gasoline or diesel. When ethanol combusts, it releases, mainly carbon dioxide and water.

C₂H₅OH + 3 O₂ → 2 CO₂ + 3 H₂O + heat

Hence, the correct option is (D).

Ether is formed when alkyl halide is heated with sodium alkoxides. This method is called Williamson's Synthesis.

Ethers can be prepared in the laboratory by Williamson's synthesis.

In this method, when an alkyl halide is treated with sodium alkoxide, the nucleophilic substitution of the halogen atom by the alkoxide group takes place.

The general example is given below.

Williamson's synthesis is used to prepare symmetrical as well as unsymmetrical ethers.

As the reaction is a nucleophilic substitution reaction, the alkyl halide should be primary alkyl halide, using secondary and tertiary alkyl halide will yield alkenes due to elimination reaction and not ethers.

It is preferable to take secondary or tertiary alkoxide ion and primary alkyl halide.

Hence, the correct option is (D).

Methanol and ethanol are distinguished by heating with iodine and alkali.

Methanol and ethanol are distinguished by a type of test known as Iodoform. When ethanol is warmed with iodine in the presence of NaOH, it forms a yellow colored precipitate but methanol do not react positively to Iodoform test.

Hence, the correct option is (C).