Nomenclature of Carbon Compounds (Given Functional Groups) MCQs Quiz | Class 10

This quiz covers Class X Science (Code 086), Unit I: Chemical Substances – Nature and Behaviour, focusing on the Nomenclature of Carbon Compounds. It tests your understanding of basic naming rules for alkanes, alkynes, halogens, alcohols, ketones, and aldehydes. Submit your answers to check your score and download the PDF solution for revision.

Educational Content: Nomenclature of Carbon Compounds

The International Union of Pure and Applied Chemistry (IUPAC) system provides a standard method for naming chemical compounds. In Class 10 Science, the focus is on naming compounds containing basic functional groups attached to carbon chains.

1. Basic Rules for Naming

To name a carbon compound correctly, follow these three steps:

  • Step 1: Identify the Longest Carbon Chain. Count the number of carbon atoms to determine the root word (e.g., 1 carbon = Meth, 2 = Eth, 3 = Prop, 4 = But, 5 = Pent, 6 = Hex).
  • Step 2: Identify the Bonding. Check if the bonds between carbon atoms are single, double, or triple.
    • Single bond: Suffix is -ane (Alkane).
    • Double bond: Suffix is -ene (Alkene).
    • Triple bond: Suffix is -yne (Alkyne).
  • Step 3: Identify the Functional Group. If a functional group is present, it modifies the prefix or suffix of the name.

2. Functional Groups and Naming Conventions

Class of Compound Functional Group Prefix / Suffix Example
Haloalkane -Cl, -Br, etc. Prefix: Chloro-, Bromo- Chloromethane
Alcohol -OH Suffix: -ol Ethanol
Aldehyde -CHO Suffix: -al Ethanal
Ketone -CO- Suffix: -one Propanone
Carboxylic Acid -COOH Suffix: -oic acid Ethanoic acid

3. Key Points to Remember

  • Numbering: Number the carbon chain such that the functional group gets the lowest possible number.
  • Terminal Groups: Aldehydes (-CHO) and Carboxylic Acids (-COOH) are always at the end of a chain. Their carbon counts as Carbon-1.
  • Alkynes: These are unsaturated hydrocarbons containing at least one carbon-carbon triple bond.
  • Vowel Drop Rule: If the suffix starts with a vowel (like -ol, -al, -one), the terminal ‘e’ of the alkane name is dropped (e.g., Propane + one becomes Propanone, not Propaneone).

4. Practice Questions

  1. Draw the structure for Butanone. (Hint: Ketone group must be inside the chain).
  2. Name the compound: CH3-CH2-Br.
  3. What is the difference between Propanal and Propanone?
  4. Write the IUPAC name for Formaldehyde (HCHO).
  5. Identify the functional group in C2H5OH.