Students should refer to the below Carbon and Its Compound Class 10 notes prepared as per the latest curriculum issued by CBSE and NCERT. These notes and questions are really useful as they have been developed based on the most scoring topics and expected questions in upcoming examinations for Class 10. Carbon and Its Compound is an important topic in Science Class 10 which if understood properly can help students to get very good marks in class tests and exams.
Carbon and Its Compound Class 10 Notes and Questions PDF Download
Read the notes below which will help you to understand all important and difficult topics in this chapter. There are some topics in Carbon and Its Compound chapter which you should understand carefully as many questions can come from those parts. Our team of teachers have designed the revision notes so that its helpful for students to revise entire course prior to the class tests.
The atomic number of carbons is 6. Its electronic configuration is 2, 4. It requires 4 electrons to achieve the inert gas electronic configuration. It can achieve noble gas configuration, If it were to lose or gain 4 electrons.
• It could gain four electrons forming C-4 anion. But it would be difficult for the nucleus with six protons to hold on to ten electrons.
• It could lose four electrons forming C+4 cations. But it requires a large amount of energy to remove four electrons.
• Thus, carbon overcomes this problem by sharing of its valence electrons with other carbon atoms or with atoms of other elements.
• The bond formed by mutual sharing of electron pairs between two atoms in a molecule is known as Covalent Bond.
Types of Covalent Bond:
• Single Covalent Bond: When a single pair of electrons are shared between two atoms in a molecule. For example; F2, Cl2, H2, HCl , H2O, CH4, NH3 etc.
• Double Covalent Bond: When two pairs of electrons are shared between two atoms in a molecule.
For example; O2, CO2 etc.
• Triple Covalent Bond: When three pairs of electrons are shared between two atoms in a molecule.
For example; N2 etc.
Allotropy is defined as the property by which an element can exist in more than one form that are physically different but chemically similar.
Allotropes of carbon
Carbon exists in three allotropic forms. They are crystalline form (diamond and graphite), amorphous form (coke,charcoal) and fullerene.
In diamond each carbon atom is bonded to four other carbon atoms forming a rigid three dimensional structure , accounting for it’s hardness and rigidity.
In graphite each carbon atom is bonded to three other carbon atoms in the same plane giving hexagonal layers held together by weak vander Waals forces accounting for softness.
Fullerenes form another type of carbon allotropes. The first one was identified to contain 60 carbon atoms in the shape of a football. (C-60).
Versatile Nature of Carbon: –
The existence of a large number of organic compounds is due to the following nature of carbon-
• Tetravalent nature.
• The self-linking property of an element mainly carbon atom through covalent bonds to form long straight, branched chains and rings of different sizes is called catenation.
This property is due to
• The small size of the carbon atom.
• The great strength of the carbon-carbon bond.
Carbon can also form stable multiple bonds (double or triple) with itself and with the atoms of other elements.
• Carbon has valency of four. It is capable of bonding with four other atoms of carbon or some other heteroatoms with single covalent bond as well as double or triple bond.
Homologous Series: A homologous series is a group or a class of organic compounds having similar structure and similar chemical properties in which the successive compounds differ by a CH2 group.
Characteristics of Homologous Series
• The successive members in homologous series differ by CH2 unit or 14 mass unit.
• Members of a given homologous series have the same functional group.
• All the members of homologous series show similar chemical properties.
• Some examples of such series are Alkanes, Alkenes, Alkynes etc
Nomenclature of Carbon Compounds
In general, the names of organic compounds are based on the name of basic carbon chain modified by a prefix (phrase before) or suffix (phrase after) showing the name of the functional group.
Following steps are used to write the name of an organic compound
Step 1 Count the number of carbon atoms in the given compound and write the root word for it .
Step 2 If the compound is saturated, add suffix ‘ane’ to the root word, but if is unsaturated, add suffix ‘ene’ and ‘yne’ for double and triple bonds respectively.
For example, CH3CH2CH3 contains three C atoms so root word is ‘prop’ and it contains only single
bonds, so suffix used is ‘ane’. Hence, the name of this compound is propane. Similarly, the compound CH3CH =CH2 is named as propene as here suffix ‘ene’ is used for double bond.
Step 3 If functional group is present in the compound, it is indicated by adding its suffix (which are given in the table above).
– Prefix ‘iso’ and ‘neo’ represent the presence of one or two carbon atoms respectively as side chain.
– If the functional group is named as a suffix, the final ‘e’ of alkane (or alkene or alkyne) is substituted by appropriate suffix.
– If the functional group and substituents are not present at first carbon, then their location is indicated by digits 1,2,3… .
CHEMICAL PROPERTIES OF CARBON COMPOUNDS
1. Combustion: – Carbon, in all its allotropic forms, burns in oxygen to give carbon dioxide along with the release of heat and light. Most carbon compounds also release a large amount of heat and light on burning.
a) C + O2 → CO2 + heat and light
b) CH4 + O2 → CO2 + H2O + heat and light
c) CH3CH2OH + O2 → CO2 + H2O + heat and light
Further, once carbon and its compounds ignite, they keep on burning without the requirement of additional energy. That’s why these compounds are used as fuels.
Saturated hydrocarbons give a clean flame due to their complete combustion whereas, unsaturated hydrocarbons give a yellow flame with lots of black smoke as they do not undergo complete combustion.
2. Oxidation: –
Carbon compounds can be easily oxidized on combustion. Oxidation is a process of intake of oxygen and removal of hydrogen. Those substances which are capable of providing oxygen to other substances are called oxidising agents such as alk. KMnO4 and acidified K2Cr2O7 .
In addition to this complete oxidation, we have reactions in which alcohols are converted to carboxylic acids .
3. Addition reaction: – Unsaturated hydrocarbons undergo addition reaction with hydrogen in the presence of nickel or palladium as catalyst to form saturated hydrocarbons.
Eg:- Ethene undergoes addition reaction with hydrogen to form ethane in the presence of nickel or palladium as catalyst
The addition of hydrogen to unsaturated hydrocarbons to form saturated hydrocarbons is called hydrogenation. Hydrogenation is used to convert unsaturated oils and fats to saturated oils and fats
4) Substitution reaction: – Saturated hydrocarbons undergo substitution reaction with halogens to form substitution products. The reactions in which a reagent substitutes (replaces) an atom or a group of atoms from the reactant (substrate) are called substitution reactions
Eg :- Methane undergoes substitution reaction with chlorine in the presence of sunlight to form substitution products.
CH4 + Cl2 → CH3Cl + HCl (in the presence of sunlight)
Some important carbon compounds: –
a) ETHANOL: – C2H5OH (Ethyl alcohol)
b) Properties: –
i) Ethanol is a colourless liquid with a pleasant smell and burning taste.
ii) It is soluble in water.
iii) Ethanol reacts with sodium to form sodium ethoxide and hydrogen.
iv) Ethanol reacts with hot conc. H2SO4 to form ethene and water. Conc. H2SO4 is a dehydrating
agent and removes water from ethanol.
i) Ethanol is used for making alcoholic drinks.
ii) It is used as a solvent.
iii) It is used for making medicines like tincture of iodine, cough syrups, tonics etc.
iv) As an anti-freeze in automobile radiators
2. ETHANOIC ACID :- CH3COOH – Acetic acid Properties :-
i) Ethanoic acid is a colourless liquid with a pungent smell and sour taste
ii) It is soluble in water.
iii) A solution of 5% to 8% ethanoic acid in water is called Vinegar.
Reactions of ethanoic acid:
i) Esterification :- Ethanoic acid reacts with ethanol to form the ester ethyl ethanoate in the presence of conc. H2SO4 . The reaction between carboxylic acid and alcohol to form an ester is called esterification
ii) Saponification: – When an ester reacts with sodium hydroxide solution, the sodium salt of the carboxylic acid and the parent alcohol are formed. This reaction is called saponification.
iii) Ethanoic acid reacts with bases to form salt and water.
iv ) Ethanoic acid reacts with carbonates and hydrogen carbonates to form salt, water and carbon dioxide.
Soaps and detergents
a) Soaps: – Soaps are long chain sodium or potassium salts of carboxylic acids.
Eg:- Sodium stearate – C17H35COONa
b) Structure of soap molecule: – A soap molecule has two parts. A long hydrocarbon part which is hydrophobic (water repelling) and soluble in oil and grease and a short ionic part which is hydrophilic (water attracting) and insoluble in oil and grease.
c) Cleansing action of soap: – When soap is dissolved in water it forms spherical structures called micelles. In each micelle the soap molecules are arranged radially such that the HC part is towards the centre and the ionic part is towards the outside. The HC part dissolves the dirt, oil and grease and forms an emulsion at the centre of the micelles which can be washed away by water
d) Detergents :- Detergents are long chain sodium salts of sulphonic acids. Soaps do not wash well with hard water because it forms insoluble precipitates of calcium and magnesium salts in hard water. Detergents wash well with hard water because it does not form insoluble precipitates of calcium and magnesium salts in hard water.
Differences between soaps and detergents: –