Free Chemistry of Hydrocarbons MCQs with Answers
1,091 Chemistry of Hydrocarbons MCQs from Chemistry, each with the correct answer and a written explanation of why it is correct. Free and unlimited, with no account needed.
Hydrocarbons are studied through the structures and reactions of alkanes, alkenes, alkynes and aromatic compounds. Coverage includes free radical substitution in alkanes, electrophilic addition to carbon-carbon multiple bonds, benzene substitution, aromatic stability and the difference between addition reactions of alkenes and substitution reactions of benzene.
Last updated
Read the Chemistry of Hydrocarbons notesFree MDCAT chapter notes with key terms1,091 questions · page 42 of 55
- A. Reaction of free radical with free radical
- B. Formation of two free radicals
- C. Consumption as well as production of another free radical
- D. Reaction between two molecules
Explanation: Propagation step involvesi) Attack of free radical on the molecule ii) Homolytic fission in the molecule iii) Bond formation.iv) Formation…
Correct answer: Consumption as well as production of another free radical- A. CI2→ 2CI
- B. CH4 +CI → CH3 +HCI
- C. CI2CH+Ci → HCCI3
- D. H3C+CI2 → H3CCI+Cİ
Explanation: Termination step in free radical substitution mechanism involvesi) Attack of free radical on other free radicalii) Bond formationiii)…
Correct answer: CI2CH+Ci → HCCI3- A. P4O10
- B. HNO3
- C. H2SO4
- D. H3PO4
Explanation: Dehydration of alcohols need dehydrating agents like concentrated H2SO4 P2O3 or P4O10.
Correct answer: HNO3- A. CH3CH=CH2 + HCI →
- B. CH3CH2CH=CH2+ HI→
- C. CH3CH=CH2 + HBr→
- D. CH3CH=CHCH3 + HBr→
Explanation: Markownikove's rule is obeyed by unsymmetrical alkenes Symmetrical alkanes like CH3CH-CHCH3 having no binding to obey the rule because…
Correct answer: CH3CH=CHCH3 + HBr→- A. CI+
- B. CI-1
- C. H+
- D. H∘
Explanation: In case of alkenes, the addition is started by the attack of electrophale.
Correct answer: H+- A. -119.5kJ/mole
- B. -358.5kJ/mole
- C. +150.5kJ/mole
- D. -208kJ/mole
Explanation: Resonance energy of benzene is +150.5 kJmol-1
Correct answer: +150.5kJ/mole827. What is required other than anhydrous AICI3 when toluene is prepared by Friedal craft reaction?
- A. C6H6
- B. C6H6+ CH3CI
- C. C6H5C2H5
- D. C6H5CI and CH3CI
Explanation: In Friedal Craft's reaction AlCl3 is a catalyst. It accelerates the reaction between C6H6 an R-X like CH3CI.
Correct answer: C6H6+ CH3CI- A. Baeyar's test
- B. Br2(CCl4)
- C. Cl2(CCI4)
- D. Tollen's test
Explanation: Tollen's reagent shows no reaction with both alkenes and alkanes. It is used to differentiate in between an aldehyde and ketone.
Correct answer: Tollen's test829. Alkanes are used as fuels. We burn them for many reasons. Which of the following is not its use?
- A. They are used to generate electricity in power stations
- B. They are used to heat our homes and cook our food
- C. They are used to provide electricity for electrolytic cell
- D. They are used to provide electricity for galvanic cell
Explanation: Explanation for this question will be added soon.
Correct answer: They are used to provide electricity for galvanic cell- A. It has a low boiling point
- B. Its enthalpy change formation (∆Ht) is positive
- C. It is susceptible to attack by nucleophilic reagent
- D. It tends to undergo electrophilic substitution rather addition reaction
Explanation: Explanation for this question will be added soon.
Correct answer: It tends to undergo electrophilic substitution rather addition reaction- A. Substitution reaction
- B. Elimination reaction
- C. Addition reaction
- D. Oxidation reaction
Explanation: Benzene cannot undergo elimination reactions.
Correct answer: Elimination reaction- A. They are electron-donating groups
- B. They increase reactivity of mono- substituted benzene ring
- C. They have all lone pair at the central atom of molecules expect alkyl group
- D. Halogeno-substituted benzene is more reactive than benzene
Explanation: Explanation for this question will be added soon.
Correct answer: Halogeno-substituted benzene is more reactive than benzene- A. Vinyl acetylene
- B. Di-vinyl acetylene
- C. Neoprene
- D. Ethylene
Explanation: When acetylene (ethyne) is passed under pressure over an organo-nickel catalyst at 70°C, the product formed is ethylene (ethylene gas).The…
Correct answer: Ethylene- A. Option A
- B. Optiion B
- C. Option C
- D. Option D
Explanation: The above molecular formula represents 4-Ethyl 1-3.4-dimethylheptane.
Correct answer: Option A- A. Reaction with hydrogen (hydrogenation)
- B. Reaction with HX (hydrohalogenation)
- C. Reaction with H20 (hyaation)
- D. All of these
Explanation: Ethene, also known as ethylene, is an alkene with a double bond between two carbon atoms. It can undergo various reactions.
Correct answer: All of these- A. Cyclohexzene
- B. Benzene
- C. Ethyne
- D. Pentene
Explanation: Explanation for this question will be added soon.
Correct answer: Cyclohexzene- A. 3-Methyl-1 -penten-4-yne
- B. 3-Methy1-4-penten-1-yne
- C. 2-Methyl-I -penten-3-yne
- D. 3-Methy1-3-penten-1-yne
Explanation: The explanation for this question will be added soon!
Correct answer: 3-Methyl-1 -penten-4-yne- A. m-Bromophenol
- B. o-and p-Bromophenol
- C. 2,4-Dibromophenol
- D. 2,4,6-Tribromoplicnol
Explanation: When phenol is treated with excess of bromine water, it gives 2,4,6-tribromophenol as the major product.
Correct answer: 2,4,6-Tribromoplicnol- A. Tetrahedral
- B. Hexagonal planer
- C. Hexagonal irregular
- D. Trigonal planar
Explanation: The structure of benzene is a planar ring of six carbon atoms, with one hydrogen atom attached to each carbon atom.
Correct answer: Hexagonal planer- A. upto 4
- B. 5 to 17
- C. 17 or more
- D. None of these
Explanation: Alkanes first five compounds are gaesous. Then next are liquids, rest are solids.
Correct answer: 17 or more