Class 10 Science


Carbon and Its Compounds NCERT Exercise Solution

Part 1

Question 1: Ethane, with the molecular formula C2H6 has

  1. 6 covalent bonds
  2. 7 covalent bonds
  3. 8 covalent bonds
  4. 9 covalent bonds

Answer: (b) 7 covalent bonds

Question 2: Butanone is a four-carbon compound with the functional group

  1. carboxylic acid
  2. aldehyde
  3. ketone
  4. alcohol

Answer: (c) ketone

Question 3: While cooking, if the bottom of the vessel is getting blackened on the outside, it means that

  1. the food is not cooked completely
  2. the fuel is not burning completely
  3. the fuel is wet
  4. the fuel is burning completely

Answer: (b) the fuel is not burning completely

Question 4: Explain the nature of the covalent bond using the bond formation in CH3Cl.

Answer: Carbon has 4 valence electrons. In order to make octet, it shares each of the four electrons with each of the three hydrogen atoms and one chloride atom. Since, bonds are formed because of sharing of electrons, hence these are covalent bonds.

structural formula methyl chloride

Question 5: Draw the electron dot structures for

(a) Ethanoic acid

Answer:

lewis dot structure ethanoic acid

(b) H2S

Answer:

lewis dot structure hydrogen sulphide

(c) Propanone

Answer:

lewis dot structure propanone

(d) F2

Answer:

lewis dot structure fluorine