Free Chemistry of Hydrocarbons MCQs with Answers

• A. Single bond
• B. Double bond
• C. Triple bond
• D. None

Explanation: When two carbon atoms share three electron pairs, they form a triple bond.

• A. Red
• B. Orange
• C. Colourless
• D. Reddish brown

Explanation: When bromine water is added to an alkene, a color change from reddish-brown (original color of bromine water) to colorless occurs.

• A. Methane
• B. Ethanol
• C. Ethane
• D. Propane

Explanation: When hydrogen is added to ethene (C2H4) in the presence of a suitable catalyst, it forms ethane (C2H6).

• A. Ethene
• B. Propene
• C. Lycopene
• D. Acetylene

Explanation: Lycopene is a carotenoid pigment present in tomatoes that gives them their red color.

• A. Single bond
• B. Double bond
• C. Triple bond
• D. Not connected

Explanation: In alkenes, the carbon atoms are connected to each other by a double bond.

• A. Hydrogen iodide is less than that of hydrogen Bromide
• B. Hydrogen Bromide is less than that of HCL
• C. Hydrogen Bromide is less than that of hydrogen iodide
• D. HCL is greater than that of hydrogen iodide

Explanation: Hydrogen Bromide is less reactive than hydrogen iodide when it comes to forming alkyl halides.

• A. phenol
• B. Ethane
• C. Propane
• D. Peopene

Explanation: The correct answer is phenol. Phenol is not colorless; it is a light pink colored liquid.

• A. C2H2
• B. C3H6
• C. C3H8
• D. C2H4

Explanation: The correct answer is C3H6, which is propene. Alkenes, such as propene, have a carbon-carbon double bond that is more reactive than single…

• A. Ethane
• B. Ethene
• C. Ethyne
• D. Methane

Explanation: Ethyne is the same as acetylene, both being alkynes with the formula C2H2. This makes it the correct answer.

• A. Alkane
• B. Alkenes
• C. Alkyne
• D. Alkyl radical

Explanation: The correct answer is option A: Alkane. Alkanes are saturated hydrocarbons with only single bonds between carbon atoms.

• A. 30 degrees
• B. 300 degrees
• C. 3000 degrees
• D. 30000 degrees

Explanation: The correct answer is option C:3000 degrees. Oxy-acetylene torches are capable of producing temperatures as high as 3000 degrees for…

• A. Ethyne
• B. Methane
• C. Propyne
• D. Butyne

Explanation: The correct answer is Ethyne, which is the simplest molecule in the alkyne homologous series with the general formula CnH2n-2.

• A. Ethylene glycol
• B. Acetylene
• C. Oxalic acid
• D. Benzoic acid

Explanation: When tetrahydroxy ethane oxidizes, it forms glyoxal, which further oxidizes to oxalic acid.

• A. Glyoxal
• B. Oxalic acid
• C. Acetylene
• D. Methane

Explanation: When Tetrahydroxy ethane loses two water molecules, it forms C2H2O2, which is Glyoxal. The correct answer is Glyoxal.

• A. One
• B. Two
• C. Three
• D. Four

Explanation: The correct answer is Option B:Two . Terminal alkynes are alkynes with the triple bond at the end of the carbon chain, while internal…

• A. Alkane
• B. Alkene
• C. Alkyl
• D. Ethanol

Explanation: The correct answer is Option B: Alkene. Alkenes and alkynes both use suffixes to indicate the presence of double or triple bonds, making…

• A. Acetylene
• B. Propanal
• C. Glycine
• D. Phenol

Explanation: Acetylene is the common name for ethyne (C2H2), which serves as the reference compound for naming alkynes as it itself is the simplest…

• A. 3s and 2p bonds
• B. 5s and 2p bonds
• C. 4s and 1p bonds
• D. 5s and 3p bonds

Explanation: Acetylene contains 3s and 2p bonds. This is because acetylene forms a triple bond between carbon atoms, consisting of 2 pi-bonds and 1…

• A. CnH2n-2
• B. CnHn-2
• C. CnH2n
• D. CnH2n+2

Explanation: The general formula of alkynes is CnH2n-2. This is because in alkynes, the number of hydrogen atoms is twice -2 than the number of carbon…

• A. Yes
• B. No
• C. Cannot say
• D. Maybe

Explanation: Alkenes are more reactive than alkynes due to their weaker Pi bonds and more exposed electrons in double bonds.