Question 11 markVery Short AnswerSection A

Name the functional group present in each of the following organic compounds : (i) C2H5ClC_2H_5Cl (ii) C2H5OHC_2H_5OH

Carbon and its Compounds
Functional Groups in Carbon Compounds

Official answer

The functional groups present in the given compounds are:


(i) C2H5ClC_2H_5Cl (Chloroethane): Halo group / Chloro group (−Cl-Cl)


(ii) C2H5OHC_2H_5OH (Ethanol): Alcohol group / Hydroxyl group (−OH-OH)

Answer keywords:ChloroHaloAlcoholHydroxyl-Cl-OH

Marking scheme

  1. 1.Identification of functional group in C2H5ClC_2H_5Cl as Chloro / Halo group (0.5 marks)
  2. 2.Identification of functional group in C2H5OHC_2H_5OH as Alcohol / Hydroxyl group (0.5 marks)

Hint

Identify the heteroatom or group of atoms replacing hydrogen in the alkane chain using Table 4.3.

Quick oral answer

The functional group in C2H5ClC_2H_5Cl is the chloro group (−Cl-Cl), and in C2H5OHC_2H_5OH, it is the alcohol group (−OH-OH).

Common mistakes

  1. 1.Writing the name of the compound instead of the functional group.
  2. 2.Confusing the alcohol group (−OH-OH) with hydroxide ion (OH−OH^-); remember that in organic compounds, it is a covalently bonded hydroxyl group.

Analysis and explanation

According to Table 4.3 of the NCERT textbook:

  • Chlorine (ClCl) acts as a heteroatom replacing a hydrogen atom in a hydrocarbon chain, belonging to the class of compounds called Haloalkanes (specifically, Chloroalkanes). The functional group is represented as −Cl-Cl.
  • Oxygen (OO) in the form of an −OH-OH group replaces a hydrogen atom to form an Alcohol. The functional group is represented as −OH-OH.

Interesting facts

Chloroethane was historically used as a mild topical anesthetic to numb skin before minor procedures due to its rapid cooling effect upon evaporation.

Question details

Q1 of 41 questions

Board
CBSE
Class
Class 10
Subject
Science
Year
2012
Section
Section A
Marks
1
Type
Very Short Answer
Chapter
Carbon and its Compounds
Topic
Functional Groups in Carbon Compounds
Bloom's level
Remembering
Syllabus topic
Functional groups in carbon compounds (Halogens, Alcohols)

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Frequently asked questions

How many marks does this question carry in CBSE Class 10 Science 2012?

This question carries 1 mark in the CBSE Class 10 Science 2012 examination.

Which chapter does this question come from in Science?

This question is from the chapter "Carbon and its Compounds" in the CBSE Class 10 Science syllabus.

What topic does this question cover in Science?

This question covers the topic "Functional Groups in Carbon Compounds" from CBSE Class 10 Science.

What type of question is this in the CBSE Class 10 Science 2012 paper?

This is a Very Short Answer question from Section A in the CBSE Class 10 Science 2012 paper.