Carbon and its Compounds ||Class 10 || Science || CBSE Notes 
Dear Students, Today we are going to share the Notes of Carbon and its Compound. These notes are prepared by the experienced teachers. These notes are free to all the students. These notes has been prepared according to the CCE pattern of school education based on NCERT Syllabus prescribed by the Central Board of School Education for Class X. All the important topics are covered in these notes. 




Some Important Topics

F Interesting Facts about Carbon
F Carbon always formed covalent Bonds
F Carbon is Tetravalent
F Self combination/Catenation
F Occurrence of Carbon
  E In free state
  E In combined state
F Allotrophy
  E Diamond
  E Graphite
  E Buckminster fullerene
F Diamond
  E Structure of diamond
  E Uses of Diamond
F Graphite
  E Structure of graphite
  E Uses of Graphite
F Buckminster fullerene
F Organic Chemistry
F Organic compound
F Types of organic compounds
  E Hydrocarbons
  E Haloalkanes
  E AlcohalsKetones
  E Aldehydes
  E Carboxylic acid
  E Reason for large number of organic compounds
F Hydrocarbon
  E Saturated Hydrocarbon
  E Unsaturated Hydrocarbon
F Alkenes
F Alkynes
  E Structural and Electronic Formula
F Alkyl Groups
F Cyclic Hydrocarbons
F Naming of Hydrocarbons
  E Single bond
  E Double bond
  E Triple bond
F Isomerism
F Homologous Series
  E Homologous series of alkanes
  E Homologous Series of alkenes
  E Homologous Series of alkynes


Interesting Facts about Carbon
Name
Carbon
Symbol
C
Status
Non-Metal
Atomic Number
6
Electronic Configuration
2, 4
No. of Valence electrons
4
No. of electrons required to attain Nobel gas configuration
4
Valency
4 (Tetravalent)
Atomic Mass
12 unit
Position in group in M.P.T
14th
Position in period in M.P.T
2nd
Bond formed
Covalent Bond
Crystalline allotrophs
Diamond, Graphite, Buckminster fullerence

Carbon always formed covalent Bonds:- 

The electronic configuration of carbon is 2, 4 . It is clear that it should either loose 4 electrons or gain 4 electrons to achieve the inert gas electron configuration.

Since carbon atom is very small. So, its electrons are strongly held by the nucleus. So, it is not possible to remove 4 electrons from a carbon atom to give it the inert gas electron arrangement. It is also not possible to add as many as 4 electrons to a carbon atom due to energy considerations.

Since Carbon atoms can achieve the inert gas electron arrangement only by the sharing of electrons, therefore Carbon always form Covalent Bonds.

Carbon is Tetravalent:

Since one carbon atom required 4 electrons to achieve the eight- electron inert gas  structure, therefore the valency of carbon is 4. That is carbon  is tetravalent ( tetra = four , valent = valency ). It is represented as
Self combination/Catenation:- 

The most outstanding or unique property of carbon its ability to combine with itself, atom to atom to form long chain.

For example Octane( C8H18 )  one of the constituent of petrol has a chain of 8 carbon atoms. This property of carbon is also known as catenation.

It has tendency to form long chains, branched chains and rings through covalent linkage. e.g.





Occurrence of Carbon: 
Carbon is unreactive element and is found in free as well as combined state.

(1) In free state:- Carbon occur in nature mainly in two forms ; diamond and graphite. Another naturally occurring form of carbon called Buckminsterfullerene has been discovered recently. Please note that only a small amount of carbon occur as free element in the earth crust. Most of the carbon occurs as free elements in the earth crust. Most of Carbon occurs in the combined state.

(2) In combined state :- Carbon occurs in nature in the form of compounds such as :- (1) Carbon dioxide gas 
(2) Carbonates like limestone marble and chalk 
(3)Fossil fuel like Coal, Petroleum and natural gas.
(4) Organic compounds such as carbohydrate, fat, protein.
(5) Wood, cotton and wool etc.

Allotrophy:- 

It is the phenomena of existence of a chemical element in two or more form called allotropes having similar chemical properties but different physical properties which is due to the difference in their structure. E.g. allotropes of Carbon

(1) Diamond
(2) Graphite
(3) Buckminster fullerene

Diamond and graphite are the two common allotropes of carbon which are known to us from centuries. Buckminster fullerene is the new allotrope of carbon which has been discovered recently.

Diamond :-  Diamond is a colourless transparent substance have extraordinary brilliant shine (chamak).  Diamond is quite heavy and extremely hard.It is the hardest known substance. It does not conduct electricity.

Diamond burn on strong heating to produce carbon dioxide. If we burn diamond in air, then only Carbon dioxide gas  is formed and nothing is left behind. This shows that diamond is made up of carbon only.

Structure of diamond :-

A diamond crystal is a giants molecule of carbon atoms.
Each carbon atom in the diamond crystal is linked to four other carbon atoms by strong covalent bond.

The diamond crystal is therefore made up of carbon atoms which are powerful bonded to one another by network of covalent bonds.Due to this, the Diamond structure is very rigid. The rigid structure of diamond make it very hard structure.

The compact and rigid three  dimensional arrangement of carbon atoms in diamond gives it is a very density. The melting point of diamond is also very high, being more than 3500 degree Celsius.

Diamond is also bad conductor of electricity, because the four valence electrons of diamond used up in forming the bonds.

Uses of Diamond:

(1) It is used for cutting and grinding other hard materials,  and also used for drilling holes in the earth’s rocky layers.

 (2) Diamond are used in cutting instrument like glass.

 Diamond dies are  also used for drawing thin wires like tungsten filament of the electric bulb.

(3) Diamond are used for making jewellery.

(4) Sharp edged diamond are used by eye surgeon as a tool to remove cataract from eyes with great precision.

(5) Diamonds can also be made artificially by subjecting pure carbon to very high pressure and temperature.

Graphite
Graphite is a greyish black diamond. Graphite is soft and slippery to touch and it conducts electricity. If we burn graphite in oxygen then only carbon dioxide gas is formed and nothing is left behind.

Structure of graphite:-

The structure of graphite is very different from that of diamond. A graphite crystal consists of carbon atoms layer or  consists of sheet of carbon atoms.
Each carbon atom in graphite is joined to three other carbon atom to form flat hexagonal ring by strong covalent bonds. Due to sheet like structure graphite is a comparatively soft substance. Due to the presence of free electron that conduct electricity.

Uses of Graphite:

(1) Due to its softness,powdered graphite is used as a lubricant for the fast moving parts of the machinery.

(2) Graphite is used for making carbon electrode or graphite electrodes in dry cell and electric arcs.

(3) Graphite is used for making the core of our pencil lead and black paint.

Buckminster fullerene: Buckminster fullerene is an allotrope of carbon containing clusters of 60 carbon atoms joined together to form spherical molecules.

Buckminster fullerene is a dark solid at room temperature.Itdiffers from other two are allotropes of Carbon, diamond and graphite as it is very small molecule made of only  60 carbon atom.

Organic Chemistry

It is the branch of Chemistry that deal with the study of organic compounds.

Organic compound :- The compound of carbon are known as organic compound expect carbonate, bicarbonate , carbide and oxide.

Some example of organic compounds:-  Methane Ethane methane ethanol ethanol etc.
Most of the carbon compound are not conductor of electricity.

Some of organic compounds

(1) Plants they give a sugar starch cellulose drugs vegetable oil insecticide which all are organic compound.

(2) Animal they give us fat protein and oil.

(3) Coal  Coal tar from coal gives us organic Compound such as Benzene Nephthelene by its destructive distillation.

(4) Petroleum:- Petroleum oil give us organic compound like petrol diesel kerosene  etc.

(5) Dead remains :- Dead remains of living organisms  give us organic Compounds

Types of organic compounds.

Some of the common type of organic   compound are
(a) Hydrocarbons
(b) Haloalkanes
(c) AlcohalsKetones
(d) Aldehydes
(e) Carboxylic acid (organic acid)

Reason for large number of organic compounds
The two main reason for large number of organic compound are(1) catenation and (2) tetravalency.

One reason for the existence of a large number of organic compounds or carbon compound is that the carbon atom can link with one another by mean of covalent bond to form a long chain which is also known as catenation.
e.g. 
Another reason for the existence of large numbers of organic compounds that the valency  of carbon is 4 and energy consideration indicate that it is the loss or gain of 4 electrons is difficult.Due to the reason carbon always form covalent bond by sharing its valency electrons with atom of other element or with itself.

Hydrocarbon:
Compound which contain hydrogen and contain carbon only are called hydrocarbon. Petroleum and natural gas are the main source of hydrocarbons. For example:- Methane Ethane propane butane pentane hexane etc.


Classification of Hydrocarbon

Saturated Hydrocarbon: Hydrocarbon in which carbon atom are connected by only single bond is called a saturated hydrocarbon (Alkanes)
General Name
Alkanes
General Formula
CnH2n + 2
Primary
― ane

Example:-  CH4 (Methane), C2H6 (Ethane), C3H8 (Propane)
Structural formula of some hydrocarbon which are saturated


Unsaturated Hydrocarbon: A hydrocarbon in which the two carbon atom are connected by a double bond or a triple bond is called an unsaturated hydrocarbon. E.g. Ethane (C2H4) and ethyne (C2H4).

Unsaturated hydrocarbon are of two types
(1) Alkenes
(2) Alkynes

(1) Alkenes:- An unsaturated hydrocarbon in which that two carbon atoms are connected by a double bond is known as alkenes. The general formula of alkenes is CnH2n where “n” is the number of carbon atom in its one molecule structure of an alkenes Ethane is as follows:

Contain  double bond (=)
Ethene (C2H4).

(2) Alkynes:- An unsaturated hydrocarbon in which the two carbon atom are connected by a triple bond is called alkyne. The general formula of alkyne is CnH2n-2 ,where n is a number of carbon atoms in one molecule. Structure formula of alkyne is as follows:-
         H ➖ C      ☰     C ➖ H
            Ethyne                contain trople bond (º)

Number of
Carbon Atoms
Word root
1
Meth
2
Eth
3
Prop
4
But
5
Pent
6
Hex
7
Hept
8
Oct
9
Non
10
Dec
11
Undec
12
Dodec

Structural and Electronic Formula of Some Hydrocarbons

Ethane:-
Ethene:  
 Ethyne:


Point to remember:- Ethane as CH3 ― H3C or H3C  ―  CH3 both are same.

Alkyl Groups:- The group formed by the removal of one hydrogen atom from an alkane molecules is called an alkyl group. Example of alkyl group or methyl (CH3‾) and Ethyl group ( C2H5‾) etc.

Please note that the free line (―) shown on the carbon atom of a alkyl group means that one valency of carbon atom is free in an alkyl group.

Cyclic Hydrocarbons

In order to the straight chain hydrocarbons and branched chain hydrocarbons there are some other hydrocarbons in which the carbon atoms are arranged in the form of a ring. Such hydrocarbon are called cyclic hydrocarbon. The cyclic hydrocarbon may be saturated or unsaturated.

(1) A Saturated Hydrocarbon is cyclohexane. The formula of cyclohexane is C6H12 

A molecule of cyclohexane contain 6 carbon atom arranged in a hexagon ring with each carbon atom having two hydrogen atom attached to it.  The structural formula of cyclohexane is shown in figure:

The saturated cyclic hydrocarbons are called cycloalkanes. Cycloalkanes with having 3 carbon atom in the ring is called cyclopropane (C3H6). The cycloalkanes with 4 carbon atom in the ring is called Cyclobutane ( C4H8).

  Please note that the general formula of the cycloalkanes is CnH2n , which is same as that of alkenes.

(2) An unsaturated cyclic hydrocarbon is benzene. The formula for benzene is C6H6. A molecule of benzene is made up of 6 carbon atoms and 6 hydrogen atoms. Structure formula is as shown in figure.

The unsaturated cyclic compound like benzene are called aromatic compounds.

Naming of Hydrocarbons

Organic compounds have two name : Common name and Official name. 

The official name or systematic name of organic compounds was given by International Union of Pure and Applied Chemistry (IUPAC) in 1958. The following number of things we keep in mind.

(1) The number of carbon atom in a hydrocarbon is indicated by using the following steps.

One atom of carbon is indicated by “Meth”
Two atom of carbon is indicated by “Eth”
Three atom of carbon is indicated by “Prop”
Four atom of carbon is indicated by “But”
Five atom of carbon is indicated by “Pent”
Six atom of carbon is indicated by “Hex”
Seven atom of carbon is indicated by “Hept”
Eight atom of carbon is indicated by “Oct”
Nine atom of carbon is indicated by “Non”
Ten atom of carbon is indicated by “Dec”

(1) A saturated hydrocarbon containing single bond is indicated by writing the word one after the stem.

(2) An unsaturated hydrocarbon containing a double bond is indicated by writing the word ene after the stem.

(3) An unsaturated hydrocarbon contain a triple bond is indicated by writing the word yne  after the stem.

Naming of Saturated Hydrocarbons

(1) Naming of CH4 :- The structure is given below
Since the compound contain one carbon atom (Meth) and single bond (saturated) hydrocarbon and indicated by ending  ane.
Therefore, IUPAC name become methane (meth + ane  = Methane).
The common name of CH4 is also Methane.

(2) Naming of C2H6 :- The structure formula of C2H6 is given below
It contains single bond and also two carbon atoms. Therefore the IUPAC name of C2H6 become (eth + ane) ethane.
Similarly IUPAC name of
(iii)   C3H8
IUPAC name:- Propane
Common name:- Propane

(iv) C4H10

IUPAC name:- Butane
Common name:- n-Butane
(v) C5H12

IUPAC name:- Pentane
Common name:- n-Pentane

IUPAC Nomenclature for Branched Chain Saturated Hydrocarbons

We should remember the following rules:-

(1) The longest chain of carbon atoms in the structure of compound is found first and name as derivative of alkanes. This is parent hydrocarbon.

(2) The alkyl group present as side chains are considered as substituent and named separately as  methyl (CH3‾) and Ethyl group ( C2H5‾) .

(3) The carbon atoms of the longest carbon atom are numbered in such a way that the alkyl group get the lowest possible number.

(4) The position of the alkyl group is indicated by writing a number of carbon atom to which it is attached.

(5) The IUPAC name of the compound is obtained by writing the position and name of parent hydrocarbon.

IUPAC name of C4 H10 :-

IUPAC name:- 2 methylpropane
Common name:- Iso butane

IUPAC name of C5H12 :-


IUPAC name:- 2 methylbutane
Common name:- Iso pentane

Naming of unsaturated hydrocarbon having double bond
Naming of C2H4
IUPAC name:- Ethene
Common name:- Ethylene

Naming of C3H6

IUPAC name:- Propane
Common name:- Propylene.

Naming of unsaturated hydrocarbon having Triple Bond
Naming of C2H2
IUPAC name:- Ethyne
Common name:- Acetylene

Naming of C3H4
IUPAC name:- Propyne
Common name:- Methyl acetylene.

Isomerism :

It is the phenomena of existence of a chemical compound in two or more forms called isomers having same molecular formula but different structural formula.
It should be notes that as the number of carbon atoms in an organic compound increase, the number of possible isomers increases rapidly.
Example:

(a) Isomers of Butane:-
(n-butane C4H10)


 (Iso-Butane C4H10)
(b) Similarly Isomers of pentane (C5H12)

Iso-pentane
2-methylbutane
Neopentane
2, 2-diamethylpropane

Isomers of Hexane: - (C6H14)



Homologous Series: 

A homologous series is a group of organic compound having similar structure and similar chemical properties in which the successive compound differ by CH2 group.
The various organic compound of a homologous series are homologues.

Example of Homologous Series:-All the alkanes have the similar structures with single covalent bond and show similar chemical properties. So they can be grouped together in the form of homologous series.

The first five members of homologous series of alkanes are given below.

(1) Methane
CH4
(2) Ethane
C2H6
(3) Propane
C3H8
(4) Butane
C4H10
(5) Pentane
C5H12

Homologous Series of alkenes:-

(1) Ethene
C2H4
(2) Propene
C3H6
(3) Butene
C4H8
(4) Pentene
C5H10
(5) Hexene
C6H12

Homologous Series of alkynes:-

(1) Ethyne
C2H2
(2) Propyne
C3H4
(3) Butyne
C4H6
(4) Pentyne
C5H8
(5) Hexyne
C6H10




Some Important Topics

Functional Group

  Halo Group

  Alcohol Group

  Aldehyde Group

  Ketone Group

  Carboxylic Acid Group

Coal and Petroleum

 ❇Coal formation

 Petroleum formation

 Substances burn with a flame or without flame

Ethanol (or Ethyl Alcohol)

  Preparation of Ethanol

 ❇ Physical Property of Ethanol

 ❇ Chemical Property of Ethanol

Combustion

Oxidation

Reaction with sodium metal

  Dehydration of Ethanol

 ❇ Uses of Ethanol

Harmful Effect of Drinking Alcohol

 ❇ Denatured Alcohol

 ❇ Test for Alcohol

 Sodium Metal Test

Easter Test

Ethanoic Acid or Acetic Acid

  Physical Property of Ethanoic Acid

 ❇ Chemical Property of Ethanoic Acid

Action on Litmus

Dilute Ethanoic

Reaction with Sodium H -Carbonate

Reaction of Ethanoic acid with Alcohols

  Uses of Ethanoic Acid

 ❇ Test for Ethanoic Acid

Shops

 ❇ Manufacture of Soap

 ❇ Structure of Soap

 ❇ Cleansing Action of Soap

 ❇ Limitation of Soap

Detergents

Functional Group

An atom or a group of atoms which makes a carbon compound (or Organic Compound) reactive and decides its properties is called a functional group.

The alcohol group – OH, present in ethanol C2H5OH, is an example of functional group. Some of the important functional groups are Halo group (or Halogeno group). Alcohol group, Aldehyde group, Ketone group, Carboxylic Acid group, Alkene group and Alkyne group. These are discussed below:

1. Halo Group :ªX (X can ve Cl, Br or I)

The halo group can be chloro- Cl, bromo – Br, or iodo- I , depending upon whether a chlorine, bromine or iodine atom is linked to a carbon atom of the organic compound.

Chloro group is present in Chloromethane CH3 ― Cl,
Bromo group is present in bromomethane CH3 ― Br
And Iodo group is present in Iodomethane CH3 ― I
The haloalkanes can be written as (R ― X ) where R is an alkyl group and X is the halogen atom.

(2) Alcohol Group:- OH

The alcohol group is made up of one oxygen atom and one hydrogen atom joined together. The alcohol group is also known as alcoholic group or hydroxyl group. The compound containing alcohol group are known as alcohols. Example of compound containing alcohols group are : methanol CH3OH, ethanol C2H5OH.
The general formula can be written as R―OH where R is alkyl group and OH is the alcohol group.

Aldehyde Group:- 

The  aldehyde group consists of one carbon atom, one  hydrogen atom and one oxygen atom joined together.

or we can say that these are the organic compound which contain ―CHO group (i.e. aldeyde group as a functional group) attached to a c―atom of an alkane molecule.

Some examples are HCHO (methanol), ethanol CH3CHO. The general formula of Aldehyde is R―CHO.

Ketone Group :
These are the organic compounds which contains ―co― group (ketone gp) as a functional group attached to a c―atom of an alkane molecule.

Some example are :- CH3COCH3 (Propanone), CH3COCH2CH3  (Butanone)
A Ketone group is always between two alkyl group. It can never be at the end of a carbon chain because it has two valency which have to be satisfied by two alkyl groups.

Carboxylic Acid Group:

These are the organic compound which contains  ― COOH group as a functional group attached to a c―atom group as a functional group attached to a c―atom of alkane.
For example:- methanoic acid H―COOH and ethanoic acid CH3―COOH.

 Coal and Petroleum

When a fuel is burned, the energy is released mainly as heat and some light, Most of the fuel which we can used today are obtained from coal, petroleum and natural gas.
Coal is complex mixture of compounds of carbon, hydrogen and oxygen and some free carbon. Small amounts of Nitrogen and sulphur compounds are also present in coal.

How Coal was formed

Coal was formed by the decomposition of large plants and trees buried under the trees million years ago. It is believed that millions of year ago, due to earthquakes and volcanoes etc, the forests were buried under the surface of the earth and got covered with sand, clay and water. Due to high temperature and high pressure inside the earth, and in the absence of air would was converted into coal.

How petroleum was formed :- Petroleum oil were formed by the decomposition of remains of extremely small plants and animals buried under  the sea millions of years ago.

Why do substances burn with a flame or without flame

(1) When the oxygen supply is sufficient then the fuel burn completely producing a blue flame. In a gas stove or cooking gas there is sufficient oxygen so produce much heat but less light. Therefore, it is said to be in non-luminous (or non light giving) flame.

(2) When the oxygen supply is insufficient then the fuels burns incompletely producing mainly a yellow flame. The yellow flame producing light so it is said to be luminous flame.

Ethanol (or Ethyl Alcohol)

Preparation of Ethanol:- Ethanol is commercially prepared by the fermentation of sugar present in the molasses by the action of enzyme called invertase and zymase secreated by yeast at a control temperature of 200 C ― 300 C

It consists of following two reaction:-
(i) 

(ii)   

The vessel used for fermentation is design in such a way that it allows CO2 to escape out of it, but does not allow the fresh air to enter into the vessel as it can oxidised Ethanol to Ethanoic acid.

Physical Property of Ethanol:-

(a) It is a colorless liquid with pleasent smell.
(b) Its boiling point is 780 C.
(c) It is lighter than water.
(d) It is soluble in water.
(e) It remains as liquid even in winter.
(f) It is neutral.
(g) It is covalent compound.
(h) It is a poor conductor of electricity.
(i) It catches fire easily.

Chemical Property of Ethanol:

(a) Combustion:- Ethanol burns in air to produce CO2 water vapours and lot of heat as

(b) Oxidation:- When ethanol is heated with alkaline potassium permanganate solution (or acidified potassium dichromate) it gets oxidized to ethanoic acid.

(c) Reaction with sodium metal :- Ethanol react with sodium to form sodium ethoxide and hydrogen gas.

Reaction with Carboxylic acids or with ethanoic acid :- Ethanol reacts with ethanoic acid in the presence of concentrated H2SO4 to produce a sweet smelling ester as ethyl ethanoate:
Dehydration of Ethanol:- When ethanol is heated with excess of conc Sulphuric acid at 1700 C , it get dehydrated to form ethane.

Uses of Ethanol

(1) Ethanol is used in the manufacture of paints, varnishes, liquiors, medicines, perfumes,  dyes, soap and synthetic rubber.

(2) Ethanol alcohol is used as a solvent. Many organic compounds which are insoluble in water are insoluble in water are soluble in ethyl alcohol.

(3) Being a good solvent, it is used in medicine such as as tincture iodine, cough syrups and many tonics.

(4) Ethyl alcohol is used as a fuel in cars along with petrol. it is used as a fuel in spirit lamps.

(5) It is used in alcoholic drinks like whisky, wine beer and other liquors.

(6) It is used as an antiscptic to sterilize wounds and syringes in hospital and dispensaries.

Harmful Effect of Drinking Alcohol

(1) Alcohol slows down the activity of nervous system and the brain due to be the judgment of a person is impaired and his reaction become slow. So a person driving a car under the influence of alcohol cannot judge a situation properly and act quickly in case of an emergency.

(2) Alcohol drinking inhabitation (mental restrain) due to which a drunken man become quarrelsome. This leads to quarrels and fights which increase violence and crime in society.

(3) Drinking alcohol heavily land of straggered movement, slurred speech, blurred vision and vomiting.

(4) Heavy drinking of alcohol over a long time may damage the stomach, liver, heart and even brain.

(5) Heavy and continuous drinking of alcohol makes the person bankrupt.

(6) The drinking of adulterated alcohol contain methyl alcohol (methanol) cause serve poisoning leading to brightness and even death.

Denatured Alcohol :- To prevent the misuse of industrial alcohol for drinking purposes (or black marketing) ethyl alcohol meant for industries is denatured by adding some amount of poisonous substance like methanol , pyridine or copper sulphate, etc. So denatured alcohol is ethyl alcohol which has been made unfit for drinking purpose by adding small amount of poisonous substance like methanol.

Test for Alcohol

(1) Sodium Metal Test:- If on adding sodium metal to the organic liquid, the bubble of hydrogen gas are produce then it indicate that the given organic liquid is ethanol.

(2) Easter Test:- If on warming solution with some glacial ethanoic acid and a few drop of cons sulphuric acid a sweet smell produced that is ester produce, it indicate that solution is ethanol.

Ethanoic Acid or Acetic Acid

Ethanoic acid can be prepared by the oxidation of Ethanol which can be done either by alkaline KMnO4 or acidic K2Cr2O7

A dilute solution of ethanoic acid in water is called vinegar. It contain 5 to 8% acetic acid.

Physical Property of Ethanoic Acid:

(a)  It is a colorless liquid having a sour taste and a pungent smell.

(b)  Its boiling point is 1180 C.

(c) Pure ethanoic acid is called glacial ethanoic acid (or glacial acetic acid).

(d) It miscible with water in all propotions.

(e) It is a good conductor of electricity.

Chemical Property of Ethanoic Acid
(a) Action on Litmus:- Ethanoic acid turn blue Litmus to Red as it produce H+ (aqions) in the solution.

(b) Dilute Ethanoic acid turn indicator paper to Orange showing that pH is about 4 which tell us that it is a weak acid.

(c) Reaction with Sodium H -Carbonate
Ethanoic acid react with sodium hydrogen-carbonate to evolve brisk effervescence of carbon dioxide gas:

This reaction is used as a test of ethanoic acid.

Reaction of Ethanoic acid with Alcohols:-

It reacts with alcohols in the presence of little of concentrated Sulphuric acid to form Easter.

Example: Easter are usually volatile liquids having sweet smell or pleasant smell.

Uses of Ethanoic Acid:

(1) Dilute ethanoic acid in the form of vinegar is used as a food preservative in the preparation of pickles and sauces.

(2) Ethanoic acid is used in the manufacture of acetone as ester used in perfumes.

(3) It is used for making cellulose acetate which is an important artificial fibre.

(4) It is used in preparation of dyes, plastics and pharmaceuticals.

(5) It is also used to coagulate rubber from latex.

Test for Ethanoic Acid:

If a pinch of sodium bicarbonate is added to ethanoic acid, the evolution of CO2 gas with brisk effervescence show that the given organic compound is carboxylic acid.

Shops

A soap is the sodium or potassium salt of long chain carboxylic acid (fatty acid) which has cleansing property in water. Example of soaps are:- Sodium Stearate and Sodium palmitate.

Manufacture of Soap:- Soap is made by heating animal fat or vegetable oil with concentrated sodium hydroxide solution (caustic soda solution) 
General reaction:

Example:-

The process of making shop by hydrolysis of fats and oil with alkalis is called saponification. The saponification gets completed soap is obtained in the form of solution. Common salt is then added to precipitate out all the soap from the aqueous solution. It decrease the solubility of due to which all the soap separate out from the solution in the form of liquid.

Structure of Soap:

A soap molecules is made up of two parts: a long hydrocarbon part and a short ionic part containing ― Coo Na+  group.
Cleansing Action of Soap:-

When Soap is dissolved in water it forms a colloidal suspension in water in which the soap molecules cluster together to form spherical misclles as in figure.

Micelle formation takes place when soap is added to water because the hydrocarbon chain of soap molecules (water repelling) which are insoluble in water but the ionic end of soap molecules are hydrophilic (water attracting) and hence soluble in water.

When the dirt cloth is agitated in soap solution, the oily and greasy particle present on its surface and entrapped by soap micelles get dispersed in water due to which the soap water become dirty but the cloth get clean.

Limitation of Soap

Following are the limitation of soap:-

(1) Soap is not suitable for washing clothes with hard water, it is because soap reacts with calcium and magnesium salts to form insoluble precipitate called scum which cloth a dirty appearance.

Detergents:

Detergents are also called soap less soaps because though they act like a soap in having cleansing properties they do not contain the usual soaps like sodium stearate etc.

Detergent are better cleansing agents than the soap because they can be used for washing even in hard water.

A detergent in the sodium salt of long chain benzene sulphonic acid (or the sodium salt of long chain alkyl hydrogen sulphate) which as cleansing properties in water.



Soap
Detergent
1
It is the sodium salt of long chain carboxylic or fatty acid which has cleansing action in water.
It is the sodium salt of long chain.
(a) Benzene Sulphonic acid.
(b) alkyl hydrogen sulphate which has cleansing action in water.
2
Example: Sodium Stearete C17H35‾ CooNa+
Example: Sodium-n-dedecyl benzene sulphonate.
3
They are obtained from animal fats and vegetable oils.
They are obtained from petroleum products.
4
They are biodegradable and hence does not cause pollution.
They are biodegradable and hence  cause pollution
5
They have relatively weaker cleansing action.
They have a stronger cleansing action.
6
They do not work well in hard water.
They work well in hard water.
7
They form scum in hard water
They do not form scum in hard water.
8
The short ionic part is CooNa+ (hydrophilic).
The short ionic part is So3 Na+ or SO4 Na+.



Post a Comment

Previous Post Next Post
Youtube Channel Image
Ndjtuition Notes Subscribe To watch more Free Handwritten Notes
Subscribe