intro
MCQs 1:
What is the product of distillation of Phenol with zinc dust?
Topic: Reactions of Phenol
Correct Answer: B) Benzene
- When Phenol is subjected to distillation with zinc dust, an important reduction reaction takes place.
- This results in the breaking down of the hydroxyl group present in Phenol and the subsequent formation of Benzene is observed.
- The product of this reaction, hence, is Benzene. As a result, the correct answer is B, "Benzene".
MCQs 2:
Of the following options, which compound exhibits the least amount of hydrogen bonding?
Topic: Hydrogen Bonding in Compounds
Correct Answer: B) Ether
- Hydrogen bonding occurs where there's a significant polarity in a molecule which allows for such interaction.
- In ethers (R–O–R’), since the oxygen atom isn't directly bonded to a hydrogen atom, the creation of a pole is usually not substantial.
- Consequently, ethers display the minimum amount of hydrogen bonding when compared to the other options. The correct answer, therefore, is B, "Ether".
MCQs 3:
In the presence of the oxidizing agents K2Cr2O7/H2SO4, what do secondary alcohols transform into?
Topic: Oxidation of Secondary Alcohols
Correct Answer: D) Ketones
- Secondary alcohols, when treated with strong oxidizing agents like K2Cr2O7/H2SO4, undergo oxidation.
- The result of this oxidation process leads to the formation of ketones.
- Hence, in the context of the question, secondary alcohols oxidize to form ketones. Consequently, the correct answer is D, "Ketones".
MCQs 4:
When tertiary alcohols are subjected to oxidation using acid dichromate, which compound is primarily formed?
Topic: Oxidation of Tertiary Alcohols
Correct Answer: A) Alkenes
- Tertiary alcohols, unlike primary and secondary alcohols, are resistant to oxidation.
- They instead undergo an elimination reaction when exposed to oxidizing agents such as acid dichromate.
- This elimination reaction leads to the formation of alkenes. Therefore, the correct answer is A, "Alkenes".
MCQs 5:
What addition to alcohol allows it to undergo the process of esterification?
Topic: Esterification Process in Alcohols
Correct Answer: C) Carboxylic acid
- Esterification is a chemical reaction that occurs between an alcohol and a carboxylic acid.
- This reaction results in the formation of an ester, often associated with fruity smells, and water as by-products.
- Therefore, for alcohol to undergo esterification, carboxylic acid must be added. Hence, the correct answer is C, "Carboxylic acid".
MCQs 6:
Which test is useful in distinguishing and identifying primary, secondary, and tertiary alcohols?
Topic: Identification of Alcohols
Correct Answer: D) Lucas test
- Several tests are available for the classification of alcohols based on their molecular weight.
- The Lucas test, which utilizes a reagent composed of anhydrous zinc chloride in concentrated hydrochloric acid, is particularly effective.
- Therefore, to distinguish primary, secondary, and tertiary alcohols, the Lucas test is used. Thus, the correct answer is D, "Lucas test".
MCQs 7:
What is the correct sequence in terms of the acidic strength of the following compounds?
Topic: Acidic Strength of Compounds
Correct Answer: C) Carboxylic acid > Phenol > Water > Alcohol
- The acidic strength of a compound is determined by its ability to donate a proton.
- In the given options, carboxylic acid is the strongest acid, followed by phenol, water, and lastly alcohol.
- Therefore, the correct sequence in terms of acidic strength is C, "Carboxylic acid > Phenol > Water > Alcohol".
Question 8:
What is the International Union of Pure and Applied Chemistry (IUPAC) nomenclature for the compound represented by CH3OH?
Topic: IUPAC Nomenclature
Correct Answer: A) Methanol
- The IUPAC nomenclature system is a set of logical rules devised for the naming of organic compounds.
- CH3OH is a simple alcohol containing one carbon atom, which in IUPAC nomenclature is referred to as 'Meth' and because it's an alcohol, the suffix 'ol' is added.
- Hence, the correct IUPAC name for CH3OH is Methanol, and the correct answer is A, "Methanol".
Question 9:
Which of the following compounds is most closely structurally related to water?
Topic: Structural Derivatives of Water
Correct Answer: D) Alcohol
- In terms of structure, alcohols can be seen as derivatives of water.
- This is because in an alcohol molecule, one hydrogen atom of a water molecule is replaced by an alkyl group.
- Given the choices, alcohols are therefore considered as derivatives of water. Thus, the correct answer is D, "Alcohol".
Question 10:
How many hydroxyl (-OH) groups does a monohydric alcohol contain?
Topic: Hydroxyl Groups in Alcohols
Correct Answer: A) One
- The term 'monohydric' refers to alcohols that contain only one hydroxyl (-OH) group in their molecular structure.
- These alcohols are the simplest form of alcohols.
- So, a monohydric alcohol contains one -OH group, making the correct response A, "One".
Question 11:
What causes the acidic nature of phenol?
Topic: Acidic Nature of Phenol
Correct Answer: A) Resonance stabilization of the phenoxide ion.
- Phenols are compounds that contain a hydroxyl group (-OH) attached to a benzene ring.
- They are more acidic than alcohols, primarily due to the resonance stabilization of the phenoxide ion.
- This stability enhances the ability of the phenol molecule to lose a proton, which accounts for its acidic nature. Therefore, the correct answer is A, "Resonance stabilization of the phenoxide ion".
Question 12:
How is Ethanol converted into Ethanoic acid?
Topic: Conversion of Ethanol to Ethanoic Acid
Correct Answer: B) Oxidation
- Ethanol can be converted into Ethanoic acid through a process known as oxidation.
- Initially, ethanol oxidizes into acetaldehyde and eventually to ethanoic acid, which has a distinctive vinegar-like smell.
- Hence, the correct process for converting ethanol into ethanoic acid is oxidation, making the correct answer B, "Oxidation".
Question 13:
What is the common name for the compound with the IUPAC name of 2-Propanol?
Topic: IUPAC and Common Names
Correct Answer: B) Isopropyl alcohol
- The compound known as 2-Propanol in IUPAC nomenclature is commonly referred to as Isopropyl alcohol.
- This naming convention is part of the common naming system that predates the standardized IUPAC system.
- Therefore, the common name for 2-Propanol is Isopropyl alcohol, making the correct answer B, "Isopropyl alcohol".
Question 14:
What forms when PCl5 reacts with an alcohol?
Topic: Reactions of Alcohols
Correct Answer: B) Alkyl halide
- When an alcohol undergoes a reaction with PCl5, it results in the formation of an alkyl halide.
- This reaction also releases hydrochloric acid and POCl3 as by-products.
- Therefore, the correct answer is B, "Alkyl halide".
Question 15:
In I.U.P.A.C. nomenclature, what is the ending suffix for alcohols?
Topic: IUPAC Naming Conventions
Correct Answer: C) -ol
- According to IUPAC nomenclature, the suffix "-ol" is used for naming alcohols.
- This signifies that the hydroxyl group is the highest priority functional group in the given substance.
- Hence, the correct answer is C, "-ol".
Question 16:
What is used to dry the remaining 4.4% water in a 95.6% rectified spirit to create 100% pure alcohol?
Topic: Purification Processes in Chemistry
Correct Answer: C) Calcium oxide
- Calcium oxide is used to eliminate the residual 4.4% water content in a 95.6% rectified spirit to produce 100% pure alcohol.
- The calcium oxide reacts with the remaining water to form calcium hydroxide.
- Consequently, the correct answer is C, "Calcium oxide".
Question 17:
What accurately characterizes a Halohydrin?
Topic: Functional Groups in Organic Chemistry
Correct Answer: A) Haloalcohol
- Halohydrin is a specific type of functional group in which a halogen and a hydroxyl are attached to adjacent carbon atoms.
- This characteristic defines it as a Haloalcohol.
- Based on the given options, the correct answer is A, "Haloalcohol".
Question 18:
In phenol halogenation, what is the name of the compound indicated?
Topic: Halogenation Reactions
Correct Answer: A) 2, 4, 6 – Tribromophenol
- The process represents the halogenation of phenol, and the marked compound is the result.
- The correct name for this resulting compound is 2, 4, 6 – Tribromophenol, which is shown to produce white precipitates.
- Therefore, the correct answer is A, "2, 4, 6 – Tribromophenol".
Question 19:
Which of the following does not fall into the category of polyhydric alcohols?
Topic: Types of Alcohols
Correct Answer: D) Option D
- Polyhydric alcohols are defined by having more than one (-OH) hydroxyl group.
- According to the provided choices, only option D represents a substance that is monohydric, meaning it only has one (-OH) group.
- Consequently, the correct answer is D, "Option D".
Question 20:
Identify the secondary alcohol from the options below:
Topic: Classification of Alcohols
Correct Answer: C) Option C
- In a secondary alcohol, the carbon atom holding the -OH group is directly linked to two alkyl groups. These alkyl groups could either be identical or different.
- After examining the options given, Option C accurately fulfills this definition.
- Thus, the correct answer is C, "Option C".
Question 21:
What is the product formed when ethanol (CH3-CH2-OH) is oxidized in the presence of potassium dichromate (K2Cr2O7) and sulfuric acid (H2SO4)?
Topic: Oxidation Reactions in Organic Chemistry
Correct Answer: B) Option B
- The stated chemical reaction illustrates the oxidation of ethanol using potassium dichromate and sulfuric acid.
- In the given options, Option B represents the correct chemical compound that results from this oxidation process.
- Therefore, the correct answer is B, "Option B".
Question 22:
Which phenol listed below exhibits the highest acidity?
Topic: Acidity of Phenols
Correct Answer: C) o-Nitrophenol
- Alkyl groups are electron-releasing and tend to decrease the acidic strength of phenols.
- However, electron-withdrawing groups like nitro enhance the acidity of phenols, especially at ortho and para positions, due to effective delocalization of negative charge in the phenoxide ion.
- Among the provided options, o-Nitrophenol demonstrates this property and is, therefore, the most acidic.
- Hence, the correct answer is C, "o-Nitrophenol".
Question 23:
Which groups of organic compounds are closely related to water in structure, and are thus considered as its derivatives?
Topic: Organic Compounds
Correct Answer: C) Alcohols, phenols, and ethers
- Organic compounds that more closely resemble water in structure are thought of as its derivatives.
- Among the options provided, the trio of alcohols, phenols, and ethers share this similarity with water due to the presence of hydroxyl or ether groups.
- As a result, the right answer would be C, "Alcohols, phenols, and ethers".
Question 24:
By which of the following tests can ethanol be distinguished from methanol?
Topic: Alcohol Identification Tests
Correct Answer: D) Iodoform test
- Ethanol and methanol can be differentiated using various chemical tests.
- Among the given options, the Iodoform test is most effective at distinguishing ethanol from methanol, due to the specific reaction of ethanol with iodine and a base.
- Therefore, the correct answer is D, "Iodoform test".
Question 25:
Which of the following compounds exhibits the greatest solubility in water?
Topic: Solubility of Organic Compounds
Correct Answer: A) C2H5OH (Ethanol)
- The solubility of organic compounds in water is largely determined by the possibility of forming hydrogen bonds with water molecules.
- Among the options given, Ethanol (C2H5OH) can form the most extensive hydrogen bonds with water due to its two carbon atoms and a hydroxyl group, making it the most soluble.
- Therefore, the correct answer is A, "C2H5OH (Ethanol)".