Importance of chemistry in our daily life

Some basic concept of chemistry 

General Introduction 

science-is derived from the Latin word Scientia" which means " knowledge " from verb " scire " which means to know. 

Science is the consecutive study of the nature, especially by experiment, observation, conclusion and the development theory or principles or scientific interferences 

or Science has been helping the man to systematize his knowledge for describing and understanding the nature. 

For Convenience, Science is subdivided into various disciplines. The main disciplines of science are:  

a).Physics- study of natural forces such as light, sound, heat, electricity, pressure etc. 

b).Biology-study of living things. 

c).Geology- study of earth. 

d). Chemistry : is the study of the materials that make up the Universe & the changes which undergo in materials.    OR     chemistry is the branch of science which deals with the composition, structure, properties of matter & interaction among them. 

• Some main branches of chemistry are - physical chemistry, organic chemistry, inorganic chemistry, industrial chemistry, analytical chemistry, Nuclear chemistry & Bit chemistry etc. 

What is the role of chemistry in the development of science in international level? -There are so many instances in our day to day that involves-

1. Supply of food: It has helped to increase the yield of foods by providing 

 a). fertilizers are used by farmers to help crops and gardens grow . 

b). Insecticide: a type of pesticide used to Kill insects 

 C). pesticides chemicals used to kill fungus ,bacteria & control pests. 

d). preservatives - to Keep food for Longer periods 

2. for better health & sanitization-chemistry provides a Large no. of lifesaving drugs such as 

a). Antipyretic: to reduce the body temperature 

 b). analgesics : Pain killer 

C). Tranquilizers . for making people feel calm or to help them sleep. 

d). Antimicrobial used to kill or control the growth the microbes. 

e). Antibiotics used to treat infections caused by germs. 

f). antifertility-used to suppress the action of hormones that promote pregnancy. 

3. for our comfort, pleasure & luxuries : - due to chemistry . It is possible that 

a). building materials  

b). synthetic fibre  

c). chemical industry: soap, detergents, 

D). alloy for articles for domestic uses. 

4. Transport & communication_ Patrol & diesel also chemicals used for vehicles. 

5. in industry : In papermaking, colour industries, lather industries etc. 

6. Nuclear chemistry  - nuclear plant  

7. In war :- Atom bomb, hydrogen bombs. 

8. environment - chemistry provides alternative way to protect our environment Such as It provide alternate chemicals of CFC used in refrigerators that harms Ozone layer.
9.  

the deleted and revised syllabus upto 30% for class ix to xii (session 2020-21) released by CBSE

Dear students,you know that cbse has reduced syllabus upto 30% for session 2020-21.Since  all world fighting with pandemic disease as COVID-19.Therfore ,All Govt in world is not oppening educational intituition school, collage and universities till vaccine has been  not come for this. So, student must be ready to continue your study /self study .otherwise ,you are making educational gap in this pandemic time . Sure, nobody can fill this if you ignore.
Be ready and be positive. think forward.........

Click here to know about the deleted and revised syllabus for class ix to xii (session 2020-21)

Click here to see the revised CBSE syllabus of class IX and X (2020-21)

                      CHEMISTRY (043) Class XI 

                                                                  DELETEDChemistry_2020-21. 

1 .  Some Basic Concepts of Chemistry Nature of matter, laws of chemical combination, Dalton's atomic theory: concept of elements, atoms and molecules. 

 

2 . Structure of Atom Discovery of Electron, Proton and Neutron, atomic number, isotopes and isobars. Thomson's model and its limitations. Rutherford's model and its limitations  

3 . Classification of Elements and Periodicity in Properties Significance of classification, brief history of the development of periodic table, 

 

4 . Chemical Bonding and Molecular Structure --

 

5.  States of Matter: Gases and Liquids liquefaction of gases, critical temperature, kinetic energy and molecular speeds (elementary idea), Liquid State- vapour pressure, viscosity and surface tension (qualitative idea only, no mathematical derivations) 

 

6 . Chemical Thermodynamics Heat capacity and specific heat capacity, Criteria for equilibrium  

7 . Equilibrium hydrolysis of salts (elementary idea), Henderson Equation 

8 . Redox Reactions applications of redox reactions

 

9 .Hydrogen Preparation, properties and uses of hydrogen, hydrogen peroxide - preparation, reactions structure and use;  

10.  s -Block Elements Preparation and Properties of Some Important Compounds: Sodium Carbonate, Sodium Chloride, Sodium Hydroxide and Sodium Hydrogen carbonate, Biological importance of Sodium and Potassium. Calcium Oxide and Calcium Carbonate and their industrial uses, biological importance of Magnesium and Calcium.  

11. Some p -Block Elements Some important compounds: Borax, Boric acid, Boron Hydrides, Aluminium: Reactions with acids and alkalies, uses. Carbon: uses of some important compounds: oxides. Important compounds of Silicon and a few uses: Silicon Tetrachloride, Silicones, Silicates and Zeolites, their uses.

 

12 . Organic Chemistry: Some basic Principles and Techniques methods of purification, qualitative and quantitative analysis 

 

13 .Hydrocarbons free radical mechanism of halogenation, combustion and pyrolysis.  

14 .Environmental Chemistry Entire chapter 

      

                             Revised COURSE STRUCTURE CLASS–XI (THEORY) (2020-21) 

Unit I: Some Basic Conceptsof Chemistry -10 Periods 

General Introduction: Importance and scope of Chemistry. Atomic and molecular masses, mole concept and molar mass, percentage composition, empirical and molecular formula, chemical reactions, stoichiometry and calculations based on stoichiometry.  

Unit II: Structureof Atom -12 Periods

 Bohr's model and its limitations, concept of shells and subshells, dual nature of matter and light, de Broglie's relationship, Heisenberg uncertainty principle, concept of orbitals, quantum numbers, shapes of s, p and d orbitals, rules for filling electrons in orbitals - Aufbau principle, Pauli's exclusion principle and Hund's rule, electronic configuration of atoms, stability of halffilled and completely filled orbitals.  

Unit III: Classification of Elements and Periodicity in Properties 06 Periods

 Modern periodic law and the present form of periodic table, periodic trends in properties of elements -atomic radii, ionic radii, inert gas radii, Ionization enthalpy, electron gain enthalpy, electronegativity, valency. Nomenclature of elements with atomic number greater than 100. 

Unit IV: Chemical Bonding and Molecular Structure 14 Periods

 Valence electrons, ionic bond, covalent bond, bond parameters, Lewis structure, polar character of covalent bond, covalent character of ionic bond, valence bond theory, resonance, geometry of covalent molecules, VSEPR theory, concept of hybridization, involving s, p and d orbitals and shapes of some simple molecules, molecular orbital theory of homonuclear diatomic molecules(qualitative idea only), Hydrogen bond.  

Unit V: States of Matter: Gases and Liquids 9 Periods 

Three states of matter, intermolecular interactions, types of bonding, melting and boiling points, role of gas laws in elucidating the concept of the molecule, Boyle's law, Charles law, Gay Lussac's law, Avogadro's law, ideal behaviour, empirical derivation of gas equation, Avogadro's number, ideal gas equation and deviation from ideal behavior.  

Unit VI: Chemical Thermodynamics 14 Periods Concepts of System and types of systems, surroundings, work, heat, energy, extensive and intensive properties, state functions. First law of thermodynamics -internal energy and enthalpy, measurement of delta U, delta H, Hess's law of constant heat summation, enthalpy of bond dissociation, combustion, formation, atomization, sublimation, phase transition, ionization, solution and dilution. Second law of Thermodynamics (brief introduction) Introduction of entropy as a state function, Gibb's energy change for spontaneous and nonspontaneous processes. Third law of thermodynamics (brief introduction).  

Unit VII: Equilibrium 12 Periods 

Equilibrium in physical and chemical processes, dynamic nature of equilibrium, law of mass action, equilibrium constant, factors affecting equilibrium - Le Chatelier's principle, ionic equilibrium- ionization of acids and bases, strong and weak electrolytes, degree of ionization, ionization of poly basic acids, acid strength, concept of pH, buffer solution, solubility product, common ion effect (with illustrative examples). 

 

Unit VIII: Redox Reactions 04 Periods 

Concept of oxidation and reduction, redox reactions, oxidation number, balancing redox reactions, in terms of loss and gain of electrons and change in oxidation number. 

 

UnitIX: Hydrogen 04 Periods 

Position of hydrogen in periodic table, occurrence, isotopes, hydrides-ionic covalent and interstitial; physical and chemical properties of water, heavy water, hydrogen as a fuel.  

Unit X: s-Block Elements (Alkali and Alkaline Earth Metals) 5 Period 

Group 1 and Group 2 Elements General introduction, electronic configuration, occurrence, anomalous properties of the first element of each group, diagonal relationship, trends in the variation of properties (such as ionization enthalpy, atomic and ionic radii), trends in chemical reactivity with oxygen, water, hydrogen and halogens, uses.

  

Unit XI: Some p-Block Elements 9 Periods 

General Introduction to p -Block Elements Group 13 Elements: General introduction, electronic configuration, occurrence, variation of properties, oxidation states, trends in chemical reactivity, anomalous properties of first element of the group, Boron - physical and chemical properties. Group 14 Elements: General introduction, electronic configuration, occurrence, variation of properties, oxidation states, trends in chemical reactivity, anomalous behaviour of first elements. Carbon-catenation, allotropic forms, physical and chemical properties.  

Unit XII: Organic Chemistry -Some Basic Principles and Techniques 10 Periods General introduction, classification and IUPAC nomenclature of organic compounds. Electronic displacements in a covalent bond: inductive effect, electromeric effect, resonance and hyper conjugation. Homolytic and heterolytic fission of a covalent bond: free radicals, carbocations, carbanions, electrophiles and nucleophiles, types of organic reactions.

  

Unit XIII: Hydrocarbons 10 Periods 

Classification of Hydrocarbons Aliphatic Hydrocarbons: Alkanes - Nomenclature, isomerism, conformation (ethane only), physical properties, chemical reactions. Alkenes - Nomenclature, structure of double bond (ethene), geometrical isomerism, physical properties, methods of preparation, chemical reactions: addition of hydrogen, halogen, water, hydrogen halides (Markovnikov's addition and peroxide effect), ozonolysis, oxidation, mechanism of electrophilic addition. Alkynes - Nomenclature, structure of triple bond (ethyne), physical properties, methods of preparation, chemical reactions: acidic character of alkynes, addition reaction of - hydrogen, halogens, hydrogen halides and water.  

Aromatic Hydrocarbons: Introduction, IUPAC nomenclature, benzene: resonance, aromaticity, chemical properties: mechanism of electrophilic substitution. Nitration, sulphonation, halogenation, Friedel Craft's alkylation and acylation, directive influence of functional group in monosubstituted benzene. Carcinogenicity and toxicity. 

                           CLASS -XII Unit Portion to be Reduced

 

1 . Solid State:- Electrical and magnetic properties. Band theory of metals, conductors, semiconductors and insulators and n and p type semi conductors.  

2.  Solutions :- Abnormal molecular mass, Van't Hoff factor  

3.  Electrochemistry Lead accumulator, fuel cells, corrosion, law of electrolysis (elementary idea), dry cell- electrolytic cells and Galvanic cells,  

4 . Chemical Kinetics Concept of collision theory (elementary idea, no mathematical treatment), activation energy, Arrhenius equation.  

5 . Surface Chemistry emulsion - types of emulsions, catalysis: homogenous and heterogeneous, activity and selectivity of solid catalysts; enzyme catalysis,  

6 . General Principles and Processes of Isolation of Elements  -Entire unit  

7 . p-Block Elements :- Preparation and properties of Phosphine, Sulphuric Acid: industrial process of manufacture, Oxides of Nitrogen (Structure only); Phosphorus - allotropic forms, compounds of Phosphorus: Preparation and properties of Halides and Oxo acids (elementary idea only).  

8.  d and f Block Elements :-Chemical reactivity of lanthanoids, Actinoids -Electronic configuration, oxidation states and comparison with lanthanoids. Preparation and properties of KMnO4 and K2Cr2O7  

9.  Coordination Compounds Structure and stereoisomerism, importance of coordination compounds (in qualitative analysis, extraction of metals and biological system).  

10. Haloalkanes and Haloarenes :-Uses and environmental effects of -dichloromethane, tri chloromethane, tetrachloromethane, iodoform, freons, DDT.  

11 . Alcohols, Phenols and Ethers :-uses with special reference to methanol and ethanol.  

12 . Aldehydes, Ketones and Carboxylic Acid ---  NOTHINGS 

13.  Amines Diazonium salts: -Preparation, chemical reactions and importance in synthetic organic chemistry.  

14.  Biomolecules:- Oligosaccharides (sucrose, lactose, maltose), polysaccharides (starch, cellulose, glycogen), importance of carbohydrates. Vitamins– classification and functions. Enzymes. Hormones - Elementary idea excluding structure.  

15 . Polymers entire chapter  

16.  Chemistry in Everyday life entire chapter 

REVISED  SYLLABUS FOR CLASS XII (2020-21) (THEORY) 

Unit I: Solid State 8 Periods 

Classification of solids based on different binding forces: molecular, ionic, covalent and metallic solids, amorphous and crystalline solids (elementary idea). Unit cell in two dimensional and three dimensional lattices, calculation of density of unit cell, packing in solids, packing efficiency, voids, number of atoms per unit cell in a cubic unit cell, point defects. 

 

Unit II: Solutions 8 Periods 

Types of solutions, expression of concentration of solutions of solids in liquids, solubility of gases in liquids, solid solutions, Raoult's law, colligative properties - relative lowering of vapour pressure, elevation of boiling point, depression of freezing point, osmotic pressure, determination of molecular masses using colligative properties.

  

Unit III: Electrochemistry 7 Periods 

Redox reactions, EMF of a cell, standard electrode potential, Nernst equation and its application to chemical cells, Relation between Gibbs energy change and EMF of a cell, conductance in electrolytic solutions, specific and molar conductivity, variations of conductivity with concentration, Kohlrausch's Law, electrolysis.

 

Unit IV: Chemical Kinetics 5 Periods 

Rate of a reaction (Average and instantaneous), factors affecting rate of reaction: concentration, temperature, catalyst; order and molecularity of a reaction, rate law and specific rate constant, integrated rate equations and half-life (only for zero and first order reactions). 

 

Unit V: Surface Chemistry 5 Periods 

Adsorption - physisorption and chemisorption, factors affecting adsorption of gases on solids, colloidal state: distinction between true solutions, colloids and suspension; lyophilic, lyophobic, multi-molecular and macromolecular colloids; properties of colloids; Tyndall effect, Brownian movement, electrophoresis, coagulation.  

Unit VII:p-Block Elements 7 Periods  

Group -15 Elements: General introduction, electronic configuration, occurrence, oxidation states, trends in physical and chemical properties; Nitrogen preparation properties and uses; compounds of Nitrogen: preparation and properties of Ammonia and Nitric Acid.  

Group 16 Elements: General introduction, electronic configuration, oxidation states, occurrence, trends in physical and chemical properties, dioxygen: preparation, properties and uses, classification of Oxides, Ozone, Sulphur -allotropic forms; compounds of Sulphur: preparation properties and uses of Sulphur-dioxide, Sulphuric Acid: properties and uses; Oxoacids of Sulphur (Structures only).

  

Group 17 Elements: General introduction, electronic configuration, oxidation states, occurrence, trends in physical and chemical properties; compounds of halogens, Preparation, properties and uses of Chlorine and Hydrochloric acid, interhalogen compounds, Oxoacids of halogens (structures only).

  

Group 18 Elements: General introduction, electronic configuration, occurrence, trends in physical and chemical properties, uses.

  

Unit VIII: d and f Block Elements 7 Periods  

General introduction, electronic configuration, occurrence and characteristics of transition metals, general trends in properties of the first row transition metals – metallic character, ionization enthalpy, oxidation states, ionic radii, colour, catalytic property, magnetic properties, interstitial compounds, alloy formation. Lanthanoids - Electronic configuration, oxidation states and lanthanoid contraction and its consequences.  

Unit IX: Coordination Compounds 8 Periods Coordination compounds - Introduction, ligands, coordination number, colour, magnetic properties and shapes, IUPAC nomenclature of mononuclear coordination compounds. Bonding, Werner's theory, VBT, and CFT.

  

Unit X: Haloalkanes and Haloarenes. 9 Periods Haloalkanes: Nomenclature, nature of C–X bond, physical and chemical properties, optical rotation mechanism of substitution reactions. Haloarenes: Nature of C–X bond, substitution reactions (Directive influence of halogen in monosubstituted compounds only).  

Unit XI: Alcohols, Phenols and Ethers 9 Periods Alcohols: Nomenclature, methods of preparation, physical and chemical properties (of primary alcohols only), identification of primary, secondary and tertiary alcohols, mechanism of dehydration. Phenols: Nomenclature, methods of preparation, physical and chemical properties, acidic nature of phenol, electrophillic substitution reactions, uses of phenols. Ethers: Nomenclature, methods of preparation, physical and chemical properties, uses.  

Unit XII: Aldehydes, Ketones and Carboxylic Acids 10 Periods Aldehydes and Ketones: Nomenclature, nature of carbonyl group, methods of preparation, physical and chemical properties, mechanism of nucleophilic addition, reactivity of alpha hydrogen in aldehydes, uses. Carboxylic Acids: Nomenclature, acidic nature, methods of preparation, physical and chemical properties; uses.  

Unit XIII: Amines 7 Periods Amines: Nomenclature, classification, structure, methods of preparation, physical and chemical properties, uses, identification of primary, secondary and tertiary amines.  

Unit XIV: Biomolecules 8 Periods Carbohydrates - Classification (aldoses and ketoses), monosaccahrides (glucose and fructose), D-L configuration Proteins -Elementary idea of - amino acids, peptide bond, polypeptides, proteins, structure of proteins - primary, secondary, tertiary structure and quaternary structures (qualitative idea only), denaturation of proteins. Nucleic Acids: DNA and RNA.