RBSE Solutions For Class 10 Science Chapter 8: Carbon and Its Compounds | Textbook Important Questions & Answers

RBSE Class 10 Science Chapter 8 Carbon And Its Compound Solutions help students to get an overview of the topics taught from Chapter 8 of Class 10 Science textbook. Carbon compounds are obtained from the living organisms. Chapter 8 of RBSE Class 10 Science, discusses in-depth concepts like Carbon compounds or Organic compounds, characteristics of carbon atoms, classification of hydrocarbons, nomenclature of organic compounds and more. Mastering these concepts and topics requires practice and hard work. For this reason, we have listed here the compilation of best questions and solutions that can help the students to prepare most efficiently for the board exams. RBSE Class 10 Solutions of Chapter 8 Science, Carbon And Its Compound help the students to know the concepts and learn the subject thoroughly.

We have given here the chapterwise list of solutions from the Class 10 Chapter 8 Science Solutions of RBSE. These questions cover all the main topics from the chapter and also consist of solutions to the questions asked at the end of the chapter in the textbook.

Rajasthan Board Class 10 Science Chapter 8- BYJU’S Important Questions & Answers

RBSE Class 10 Science Chapter 8 Objective Questions-Important Questions and Solutions

1. The value of bond angle in methane is____

(a) 109°28′

(b) 120°

(c) 180°

(d) 105°

Answer: (a) 109°28′

2.C5H10 hydrocarbon is __

(a) Pentane

(b) Pentene

(c) Pentyne

(d) Pentadiene

Answer: (b) Pentene

3.The formula of Freon-11 is _____

(a) CFCl3

(b) C2F2Cl4

(c) CF2Cl2

(d) C2F4Cl

Answer: (a) CFCl3

4. Natural Rubber is polymer of_____

(a) Neoprene

(b) Isoprene

(c) 1,3-Butadiene

(d) Buna-N

Answer: (b) Isoprene

5. Which allotrope of carbon is a good conductor of electricity?

(a) Diamond

(b) Graphite

(c) Fullerene

(d) Coke

Answer: (b) Graphite

6. To improve the quality and tensile strength of natural rubber, it is heated with sulphur. This process is known as______

(a) Polymerization

(b) Saponification

(c) Vulcanisation

(d) Equalization

Answer: (c) Vulcanisation

7. If the number of carbon atoms is 3, then the prefix used is____

(a) Eth-

(b) Prop-

(c) But-

(d) Pent-

Answer: (b) Prop-

8. The IUPAC name of CH2=CH-CH2-Cl is _____

(a) 1 – Chloro – 2 – propene

(b) Prop – 1 – chloro – 2 – ene

(c) 3 – Chloro – 2 – propene

(d) 3 – Chloro – 1 – propene

Answer: (d) 3 – Chloro – 1 – propene

RBSE Class 10 Science Chapter 8 Very Short Answer Questions-Important Questions and Solutions

1.Write the general formula for alkanes, alkenes and alkynes.

Answer: The general formula for an alkane is CnH2n+2.. Similarly, the general formula for alkene and alkyne are CnH2n and CnH2n-2.

2. Hydrocarbons are made up of which two elements?

Answer: The compound Hydrocarbons are made up of the two elements, Hydrogen and carbon.

3. Write the full name of IUPAC.

Answer: The full form of IUPAC is known as the International Union of Pure & Applied Chemistry.

4. Give the definition of vulcanization

Answer: The process of heating the sulphur to improve the quality and the tensile strength of natural rubber is called vulcanization.

5. How many carbon atoms are possible in Fullerene?

Answer: Fullerene is denoted as C60 or C70. Fullerene molecule possesses 60 to 70 carbon atoms.

6. What type of geometry is present in the Carbon atom?

Answer: Carbon is tetravalent in nature with 4 valencies oriented towards four corners of a regular tetrahedron. Carbon atom is located at the centre of the tetrahedron with the bond angle of 109°28′ between each valency.

7. Write the definition of Freon.

Answer: Freons are the “polychlorofluoroalkanes”. Compounds in which carbon atoms are linked with chlorine and fluorine are known as chlorofluorocarbons (CFC) or Freons.

8. Name the scientist who synthesized the first organic compound.

Answer: The scientist, Friedrich Wohler synthesized the first organic compound urea by heating a mixture of inorganic compounds, ammonium sulphate and potassium cyanate in the laboratory.

9. Write the full form of CNG.

Answer: CNG is the short form of Compressed Natural Gas, which is created by compressing natural gas at high temperature.

10. Give the name of monomers by which orlon is formed by the polymerization process.

Answer: Poly Acrylonitrile or Orlon is formed by polymerizing the monomer vinyl cyanide or Acrylonitrile.

11. Name the allotropes of Carbon.

Answer: There are two main allotropes of Carbon. 1) the Crystalline allotropes and 2) the Amorphous allotropes. Diamond, Graphite and Fullerene are the main crystal allotropes of Carbon. Meanwhile, Coal, Coke, Wood, Carbon, Gas, Charcoal and so on are also examples of the Amorphous or non-crystalline allotropes.

12. Write the IUPAC name of Isobutane.

Answer: An isomer of butane, Isobutane is a chemical compound with the molecular formula HC(CH3)3 and is also known as i-butane, 2-methylpropane or methylpropane.

13. Write the full name of PAN.

Answer: Poly Acrylonitrile is the full form of PAN.

14. By polymerization of which monomer, PVC is formed?

Answer: Poly vinyl chloride is produced by polymerizing the monomer, vinyl chloride.

RBSE Class 10 Science Chapter 8 Short Answer Questions-Important Questions and Solutions

15. Write three differences between diamond and graphite.




Diamond is hardest among the known subjects

Graphite is soft and smooth

It is bright, shiny and transparent

It is grey black substance

Diamond is a non-conductor of heat and electricity

Graphite is a good conductor of heat and electricity

16. What do you understand about the catenation tendency of carbon items?

Answer: Carbon atoms possess a special ability which enables them to bond itself, thus forming branched, unbranched or cyclic chains of carbons to carbon bonds. This property of the carbon atom is known as catenation.

17. Write the IUPAC name and structural formula of the following:

(i) C5H12

(ii) C4H8

(iii) C3H4

Answer: (i) Pentane is IUPAC name for C5H12, while the structural formula for it is CH3-CH2-CH2-CH2-CH3.

(ii) C4H8 is Cyclobutane and the structural formula is
cyclobutane structural formula .

(iii) Cyclopropene is the IUPAC name for C3H4. Structural formula for this is
Cyclopropene Structural Formula

18. Write two uses of freon.

Answer: Given here are two uses of freons:

(i) Freons are used as inert solvents

(ii) Freons are used as refrigerants or coolants in refrigerator, air conditioner and cold-storages.

19. Why is CNG better than LPG as a fuel?

Answer: CNG is safer than LPG as it is lighter than LPG. So, when there is a CNG leakage it spreads out in the air, while LPG is heavier so it collects in lower layers, thus increasing the chance of accident. Also, since CNG has less percentage of Carbon, its combustion results in lesser amount of Carbon monoxide or Carbon dioxide. For this reason, CNG is less harmful. Learn more about the differences between CNG and LPG here.

20. Why is diamond hard and graphite soft?

Answer: The carbon atom in diamond bonds with four other carbon atoms, resulting in the strong tetrahedral arrangement. Meanwhile, in graphite, a carbon atom bonds with three other carbon atoms, leading to the formation of hexagonal ring structure. Sheets of graphite can slip over one another due to the presence of weak bonds. Hence, diamond is hard but graphite is soft.

21. Write any four characteristics of fullerene.

Answer: Four features of Fullerene are given:

(i) Fullerene has a structure similar to the football

(ii) The molecule of Fullerene contains C60, C70 or more carbon atoms

(iii) The most stable Fullerene, C60 called Buckminister Fullerene contains a total of 32 faces, out of which 20 are hexagonal and 12 pentagonal. It has a football structure, hence known as Buckyball

(iv) C60 is a non-conductor of electricity and carbon bond distance in C60 is 1.46 Å

22. Draw the sketch of classification of hydrocarbons.


classification of hydrocarbons

If you wish to know more about the classification of hydrocarbons as well as the types and properties of hydrocarbons, check out the Hydrocarbons article.

23. Write the uses of graphite.

Answer: Given below are the uses of graphite:

  • It is used in our pencils, for writing purposes
  • It is used as a dry lubricant
  • It is also a good conductor of electricity so it is used to make electrodes
  • Used to polish things made of iron
  • Also used as a moderator in nuclear atomic reactor

24. Write the main characteristics of Carbon Atom.

Answer: Given here are the main characteristics of Carbon Atom:

1. Atomic Number of Carbon is 6 in the periodic table and is denoted as ‘C”

2. The electronic configuration of a carbon atom is 1s2 2s2 2p2

3. The valency of a carbon atom is 4. Carbon atoms can combine with other atoms to balance its four valencies.

4. Carbon atoms possess a special ability which enables them to bond itself, thus forming branched, unbranched or cyclic chains of carbons to carbon bonds. This property of the carbon atom is known as catenation.

5. Carbon atoms can form single, double and triple bonds combined with other carbon atoms.

6. Carbon atoms can form a covalent bond with the hydrogen atom by equal sharing of electrons due to almost the same electronegativities for both.

7. Carbon has 3 naturally occurring isotopes (12C and 13C – stable, 14C – radioactive)

8. Carbon has a high melting point and can easily combine with oxygen at elevated temperatures.

9. The radioactive isotope of carbon is C-14, which is used to date ancient objects of organic origin.

25. Write the IUPAC Names of the following.

(i) Iso-octane

(ii) RBSE Class 10 Science Chapter 8 question 26

(iii) Neopentane

(iv) RBSE Class 10 Science Chapter 8 Question 26 -1

Answer: (i) The IUPAC name for Iso-octane is 2,2,4-Trimethylpentane

(ii) 2-methylpropene is the IUPAC name

(iii) 2,2-dimethylpropane is the IUPAC name for Neopentane

(iv) IUPAC name is 2-bromo-3-chloro butane

26. What is plastic? Write names of main plastic polymers.

Answer: Polymer of simple organic molecules that can be moulded into solid objects is called plastic. Examples of plastic include PVC, polythene, orlon, polystyrene and so on.

27. Write the utilities of diamond and fullerene.

Answer: The use of diamond are as follows:

(i) It is used as a glass cutter

(ii) Used in machines that are used to cut rocks and stones

(iii) It is used in making phonogram needles

(iv) Used in making gems and jewellery

Meanwhile, the uses of fullerene is also given here:

(i) Used in purification of natural gas

(ii) It is used in molecular bearing

(iii) An important allotrope of carbon, it behaves like a super conductor at higher temperature.

28. Explain the nomenclature of Freon.

Answer: The number of carbon, hydrogen and fluorine atoms in the molecular formula of freon are used for the nomenclature of freons as follows:

Freon= XYZ here.

(i) X- one less than the number of carbon atoms in freon molecule (C-1)

(II) y-One more than the number of hydrogen atoms in the freon molecule (H+1)

(iii) Z- Number of fluorine atoms in the freon molecule.

RBSE Class 10 Science Chapter 8 Essay Questions-Important Questions and Solutions

29. What do you mean by synthetic polymers? Write their process of synthesis and uses.

Answer: Polymers that are made in a laboratory or factory are known as synthesized polymers. Some examples are given here:

Nylon-66: Made after condensation of adipic acid (6-carbon) and hexamethylenediamine (6-carbon), this is called nylon-66. It is used for manufacturing gear and bearing in machines, tyre, cloth, fibre, ropes, toothbrush, and so on.

Terylene: Obtained by condensation of ethylene glycol and terephthalic acid, it is also called decron and is used to manufacture cloth, sail, belt, magnetic tape, film and so on.


Rayon:To make rayon, paper (cellulose) is dipped in sodium hydroxide solution and cleaned. After that, it is dissolved in carbon disulphide. This solution is passed through the pores and collected in dilute sulphuric acid. The process gives fine shiny fibres of rayon and is used to manufacture cloth, threads, carpets and so on


Polythene: Ethylene is subjected to polymerization under high temperature in presence of catalyst to obtain polythene. This is flexible and strong plastic. It is used for making bags, bottles, pipe, tube and more.

Poly vinyl chloride: Obtained by polymerisation of vinyl chloride. It is used for making pipe, shoes, slippers, bags, raincoat, toys, phonogram record, insulating layer, etc.

Poly acrylo nitrile: obtained by polymerization of vinyl cyanide and is used for making sweater, woollike, fibre, pillow, quilt,and so on.

Polystyrene: This is obtained by polymerization of vinyl benzene (styrene) and is used in the manufacture of cups, bottle caps, refrigerator parts, wall tiles, packing materials and more.

30. Write a note on the following:

(i) Freon

(ii) CNG

(iii) Natural Rubber

Answer: (i) Polychloroflouroalkenes are called Freon and they are used as refrigerants. Production of Freon: Carbon tetrachloride reacts with hydrogen fluoride in the presence of antimony pentachloride to give Freon-11.

RBSE Class 10 Science Chapter 8 question 30 solution

Find more about Freon.

(ii) When natural gas is compressed it is called Compressed Natural Gas (CNG). CNG present above the oil layer in oil wells is termed as natural gas. CNG has less amount of carbon and so it produces negligible amount of carbon monoxide or carbon dioxide on combustion. For this reason, CNG is more environment-friendly than other petroleum products. It is used as a fuel and also as an alternative to petrol and diesel in the vehicle used for transportation.

(iii) Natural Rubber is obtained from latex which is a sap of a tree. Natural rubber is a polymer isoprene. Acetic acid is added to latex to make it solid. Rubber obtained by this process is highly elastic and has less tensile strength. This is not suitable for making useful products. To make it useful, rubber is heated with sulphur and the process is called vulcanization. Rubber obtained after vulcanization is strong, inelastic and more durable. Learn more about Natural Rubber and its properties here.

31. (a) Write the main rules applied in nomenclature of alkanes.

(b) Write the formula for the following:

(i) Neopentane

(ii) Isopentane

(iii) 1, 3-Dichloropropane

(iv) 3-Ethyl-4-methylhexane

(v) 3-methyl-1-butene

Answer: The main rules applied in nomenclature of alkanes are as follows:

  • The longest carbon chain is selected for naming. The Atom or Group that remains out of the main chain is called substituent.
  • If two or more chains of same length are present then the chain with greater number of substituents is selected.
  • Name of the substituent is written first and then the prefixes are written in alphabetical order.
  • If the number of identical substituents are more than one in a molecule, then the number of identical substituents are denoted as mono, di, tri, tetra, penta, Hexa, Hepta, Octa, Nona and Decca.
  • Minimum number is given to the substituents. If two substituents are symmetrically placed on the carbon chain, then the substituent coming first in the alphabetic order is given the lowest position numbers.
  • At the time of writing the name of an organic compound a comma is given between two numbers and a hyphen is used between a numeral and the name of the compound.

(b) (i) Neopentane is also called 2,2-dimethylpropane and has a molecular formula C5H12

RBSE Class 10 Science Chapter 8 Question 32 Solution-1

(ii) C5H12is the molecular formula for Isopentane.

RBSE Class 10 Science Chapter 8 Question 32 Solution-2

(iii) Molecular formula for 1, 3-Dichloropropane is C3H6Cl2.

RBSE Class 10 Science Chapter 8 Question 32 Solution-3

(iv) C9H20 is the molecular formula of 3-Ethyl-4-methylhexane.


| |

C2H5 CH3

(v) C5H10 is the molecular formula for 3-methyl-1-butene




RBSE Class 10 Science Chapter 8 Additional Questions-Important Questions and Solutions

32. Covalent compounds have low melting and boiling points. Give reason.

Answer: Intermolecular forces between the covalent compounds are small because the covalent bond is created by sharing equal electrons between two atoms. These bonds break easily.

33. Write two uses of methane gas.

Answer: The uses of methane gas are as follows:

(i)Used as a fuel

(ii)A major component of biogas and CNG.

34. Give the reason why carbon creates compounds chiefly by covalent bonding.

Answer: Carbon easily creates compounds mainly via covalent bonding as carbon is of small size and so it is not possible for it to lose four electrons easily. Gaining the four electrons will also not be easy. It will need a high amount of energy to lose as well as to gain four electrons. Hence, it shares four electrons forming covalent bond

35.Carbon forms a large number of compounds. Why?

Answer: Carbon has tetravalency and catenation features that enable it to form a large number of compounds. Carbon has valency 4, hence, to attain noble gas configuration carbon shares its valence electrons with other elements such as hydrogen, chlorine and more. Likewise, Carbon also adapts the self-linking property using which it forms long, branched or cyclic chains of a large number of compounds.

36. Diamond and graphite have different physical properties even if they are made up of carbon and show the same chemical properties. Why? What is this property called?

Answer: The property where diamond and graphite show different physical properties even if they are made up of carbon and have the same chemical properties is allotropy. Because the carbon-carbon bonding in both the cases vary, the physical properties are different. In diamond, one carbon atom bonds with four other carbon atoms of strong covalent bond. This also makes it hard. Meanwhile, in case of graphite, each carbon creates three strong bonds with other three atoms to create a sheet of hexagonal rings. This results in a weak bond between the rings that can slide over each other. Hence, graphite is soft.

After reading through Rajasthan Board 10 Class Science Book, students must attempt the Rajasthan Board Class 10 previous years question papers to understand the RBSE Science paper pattern.

Stay tuned for more updates on Rajasthan Board exam. Download BYJU’S App and subscribe to Youtube channel to watch interactive maths and science videos for your studies.

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