All Free Chemistry MCQs with Answers

• A. Rropylene
• B. Propane
• C. Propene
• D. Propanol

Explanation: Alcohol reacts with PCl3 to form Alkyl Halides by nucleophilic substitution reaction forming akene (reaction shown below):

• A. Water
• B. Ethyl alcohol
• C. Ammonia
• D. Carbon tetrachloride

Explanation: CCl4 is non polar so as ethene is... They dissolve in each other perfectly because of same nature

• A. water
• B. ethyl alcohol
• C. ammonia
• D. carbon tetrachloride

Explanation: CCl4 is non polar so alkene dissolves in it best LIKE DISSOLVES LIKE. As, alkenes is non polar so it will dissolve in non polar solvent

• A. Less susceptible to oxidation
• B. More susceptible to oxidation
• C. Equally susceptible to oxidation
• D. All of these

Explanation: A carbon-carbon double bond represents unsaturation, while a single carbon-carbon bond represents saturated hydrocarbons, alkanes that are…

• A. Addition of bromine water
• B. Addition of HI
• C. Oxidation with ozone
• D. All of the above

Explanation: Ozonolysis, i.e., oxidation with ozone, is the method used to point out the position of a double bond in an organic compound.

• A. 1-pentene
• B. 2-pentene
• C. 2-Methyl-1-butene
• D. 3-Methyl-1-butene

Explanation: The reaction of alkenes with bromine proceeds through the formation of a carbocation intermediate.

• A. 4- Methyl-1-Pentene
• B. 2- Methyl-3- Pentene
• C. 2- Methyl-2- Pentene
• D. 4,4-Dirnethyl-2-Pentene

Explanation: According to the IUPAC system of naming compounds, the methyl group is the substituent that will have secondary importance because the…

• A. C5 H22
• B. C5 H10
• C. C5 H8
• D. C4 H10

Explanation: The general formula for alkenes is CnH2n, where n=5 is the formula for alkene C5H10

• A. C2H4 > C2H2 > C6H6
• B. C6H6 > C2H4 > C2H2
• C. C2H4 > C2H4 > C6H6
• D. C2H2 > C6H6 > C2H4

Explanation: In electrophilic addition reactions, the reactivity order is C2H4 (alkene) > C2H2 (alkyne) > C6H6 (benzene).

• A. CH3CHO + CH3CHO
• B. CH3CH2CH2CH2 - OH
• C. CH3CH2CH2COOH
• D. CH3CH2COCH3

Explanation: The correct answer is D:CH3CH2COCH3. When water is added to an alkyne, it typically undergoes a hydration reaction resulting in the…

• A. Hex-2-ene
• B. Hex-3-ene
• C. 2-methyl pent-1-ene
• D. 2-methyl pent-2-ene

Explanation: d) 2-methyl pent-2-ene:2-methyl pent-2-ene is a five-carbon alkene with a methyl group attached to the second carbon atom and the double…

• A. CH3-CH-CH2O ⋮ ClOHCl
• B. CH3-CH-CH2Cl ⋮ OH
• C. CH3-CH2-CH2Cl ⋮ OH
• D. CH3-CH-CH2 ⋮ OH

Explanation: The reaction between propene and hypochlorous acid (HOCl) can be represented as follows:CH3CH=CH2 + HOCl → CH3CH(OH)CH2ClThe product…

• A. Methane
• B. Ethylene
• C. Ethane
• D. None of the above

Explanation: Option d) "None of the above" is incorrect because ethylene (option b) decolorizes KMnO4 but does not give a precipitate with ammoniacal…

• A. 2 - Butene
• B. 2,3 di Methyl-2 Pentene
• C. 2 - Pentene
• D. 1 - Hexene

Explanation: The longest carbon chain is of 5 carbons so the name ends with pentene and since there are two methyl groups as branches so option B is…

• A. Alkanes > Alkenes > Alkynes
• B. Alkynes > Alkenes > Alkanes
• C. Alkenes > Alkynes > Alkanes
• D. Alkenes = Alkynes > Alkanes

Explanation: The order of decreasing reactivities for alkanes, alkenes, and alkynes is as follows: alkynes > alkenes > alkanes.

• A. 1-chloro 1-butanol
• B. 2-chloro 1-butanol
• C. Both (A) and (B)
• D. None of the above

Explanation: When hypochlorous acid (HClO) reacts with 1-butene, the main product formed is 1-chloro-1-butane.

• A. 2-Pentanone
• B. pentanol
• C. 3-Pentanone and Ethanal
• D. 7-Heptanone

Explanation: When 3-Ethyl-2-Pentene undergoes ozonolysis, it reacts with ozone (O3) to form two pentanone molecules.

• A. cis-2-butene
• B. Isobutylene
• C. trans-2-butene
• D. 1-butene

Explanation: trans-2-butene is the most stable option among the given choices because it has a straight-chain configuration with no steric…

• A. CH4
• B. C2H2
• C. C2H4
• D. C2H6

Explanation: Metallic carbide/Calcium Carbide: CaC2 Calcium carbide on hydration gives acetylene.

• A. C2H6
• B. C2H4
• C. C2H2
• D. C6H6

Explanation: Only alkynes can perform this reaction. 2[Cu(NH)3]OH + HC≡CH → Cu−C≡C−Cu + 4NH3 + 2H2O copper acetylide Red ppt.