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.
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Read the Chemistry of Hydrocarbons notesFree MDCAT chapter notes with key terms1,091 questions · page 12 of 55
- A. CH3Cl
- B. CCl4
- C. CH2Cl2
- D. CHCl3
Explanation: CH3Cl is chloromethane.CH2Cl2 is dichloromethane.CHCl3 is trichloromethane (chloroform).CCL4 is tetrachloromethane (Carbon Tetrachloride).
Correct answer: CHCl3- A. CnH2n+2
- B. CnH2n
- C. CnH2n-2
- D. CnHn
Explanation: General formula for both alkenes and cyclo-alkanes is CnH2n.
Correct answer: CnH2n- A. Cyclohexene
- B. Cyclobutane
- C. Toluene
- D. Cyclopentene
Explanation: The homocyclic compounds which contain a ring of three or more carbon atoms and resembling aliphatic compounds are called alicyclic…
Correct answer: Toluene- A. Decolorization of red Br2 water in CCl4
- B. Decolorization of pink colour of KMnO4 solution
- C. Ozonolysis
- D. All
Explanation: Identification tests for unsaturation:Decolorization of Br2 water.Hydroxylation of alkenes by dilute alkaline KMnO4 solution (pink color…
Correct answer: All225. The addition of unsymmetrical reagent to an unsymmetrical alkene is in accordance with the rule:
- A. Hund's rule
- B. Mankownikov's rule
- C. Pauli's exclusion principle
- D. Aufbau principle
Explanation: The addition of hydrogen halide over an unsymmetrical alkene is governed by Markownikov's Rule.
Correct answer: Mankownikov's rule- A. Alkenes
- B. Alkynes
- C. Alkanes
- D. All of them
Explanation: Vicinal dihalides have two halogens on adjacent carbon atoms. Dehalogenation occurs when dihalide is treated with Zinc dust in an…
Correct answer: Alkenes- A. Pb(BaSO4) / Quinoline
- B. Ba(PbSO4) / Quinoline
- C. Pd(BaSO3) / Quinoline
- D. Pd(BaSO4) / Quinoline
Explanation: Controlled hydrogenation of alkynes with hydrogen gas in an equimolar ratio over heated catalysts, gives alkenes.
Correct answer: Pd(BaSO4) / Quinoline- A. Chloroform
- B. Acetylene
- C. Divinyl acetylene
- D. Chloroprene
Explanation: When acetylene is passed through an acidic solution of cuprous chloride and ammonium chloride and then allowed to stand for several hours…
Correct answer: Chloroprene- A. 2-pentyne
- B. Ethene
- C. 2-butyne
- D. Ethyne
Explanation: In ethyne and other terminal alkynes like propyne, the hydrogen atom is bonded to the carbon atom with sp-s overlap.
Correct answer: Ethyne- A. Propane
- B. Butane
- C. Benzene
- D. Napthalene
Explanation: When acetylene is passed through a copper tube at 300°C, it polymerizes to benzene.
Correct answer: Benzene- A. 2
- B. 3
- C. 4
- D. 5
Explanation: Xylene (dimethyl benzene) has three isomers namely orthoxylene, metaxylene and paraxylene.
Correct answer: 3- A. 1
- B. 2
- C. 3
- D. 4
Explanation: Acidic hydrogen is where hydrogen can easily form H+ . Hydrogen attached to triple bonded carbon is easily removable.
Correct answer: 1- A. 1% alkaline KMnO4
- B. 1% acidic KMnO4
- C. 15% alkaline KMnO4
- D. 2% alkaline KMnO4
Explanation: (1%) alkaline KMnO4 solution (Baeyer's Reagent)
Correct answer: 1% alkaline KMnO4- A. Ethene
- B. Ethyne
- C. Methane
- D. Both (a) and (b)
Explanation: Ethene (C₂H₄) - also called ethylene - is a plant hormone that triggers:Fruit ripening 🍌🍅🍎Flower openingLeaf fall (abscission)It is…
Correct answer: Ethene- A. Alkaline KMnO4
- B. O3
- C. H2SO4
- D. K2Cr2O7
Explanation: When alkenes are treated with mild oxidizing reagents like dilute (1%) alkaline KMnO4 solution (Baeyer's Reagent) at low temperature…
Correct answer: Alkaline KMnO4- A. Rotten egg
- B. Garlic
- C. Spicy like
- D. None of the above
Explanation: Information based. Alkynes are colourless, odourless, except acetylene which has a garlic like odour,
Correct answer: Garlic- A. Ethanal
- B. Methanal
- C. Methanol
- D. Ethanol
Explanation: Ozonolysis of ethene produces unstable ethylene molozonide which upon treatment with Zn/H2O forms formaldehyde or methanal.
Correct answer: Methanal- A. Saturation
- B. Unsaturation
- C. Substitution
- D. None
Explanation: Presence of double bond indicates unsaturation. Tests for detection of unsaturation include:Test with Bromine water.Test with Baeyers…
Correct answer: Unsaturation- A. Polyacetylene
- B. Benzene
- C. Chloroprene
- D. Divinylacetylene
Explanation: When acetylene is passed through an acidic solution of cuprous chloride and ammonium chloride and then allowed to stand for several hours…
Correct answer: Chloroprene240. The addition of unsymmetrical reagent to an unsymmetrical alkene is is accordance with the rule:
- A. Hund's rule
- B. Markownikov's rule
- C. Pauli's exclusion principle
- D. Aufbau principle
Explanation: The addition of hydrogen halide over an unsymmetrical alkene is governed by Markownikov's Rule.
Correct answer: Markownikov's rule