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You haven't mention the class and board, which class and board  you want to know the deleted syllabus of chemistry. Please mention the class and board it is quite easy to give answer, if the question is complete:-

If you want to know the deleted portion of 11th Chemistry CBSE board then :-

• Some Basic Concepts of Chemistry :- Nature of matter,  laws  of chemical  combination,  Dalton's  atomic theory: concept of elements, atoms and molecules
• 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
• Classification of Elements and Periodicity in Properties :- Significance of classification, brief history of the development of periodic table
• 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)
• Chemical Thermodynamics :- Heat capacity and specific heat capacity, Criteria for equilibrium
• Equilibrium :- Hydrolysis of salts (elementary idea), Henderson Equation
• Redox Reactions :- Applications of redox reactions
• Hydrogen :- Preparation, properties and uses of hydrogen, hydrogen peroxide - preparation, reactionsand structure and use;
• 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.
• 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.
• Organic Chemistry: Some basic Principles and Techniques :- Methods of purification, qualitative and quantitative analysis
• Hydrocarbons :- Free radical mechanism of halogenation, combustion and pyrolysis.
• Environmental Chemistry :- Entire chapter

Class 12th CBSE board deleted portion:-

• Solid State :- Electrical and magnetic properties. Band theory of metals, conductors,  semiconductors  and   insulators and n and p-type semiconductors.
• Solutions :- Abnormal molecular mass, Van't Hoff factor
• Electrochemistry :- Lead accumulator, fuel cells, corrosion, law of electrolysis (elementary idea), dry cell- electrolytic cells and Galvanic Cells
• Chemical Kinetics :- Concept of collision theory (elementary idea, no mathematical treatment), activation energy, Arrhenius equation
• Surface Chemistry :- Emulsion - types of emulsions, catalysis: homogeneous and heterogeneous, activity and selectivity of solid catalysts; enzyme catalysis
• General Principles and Processes of Isolation of Elements :- Entire unit
• 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).
• d and f Block Elements : - Chemical reactivity of lanthanides, Actinides -Electronic configuration, oxidation states and comparison with lanthanide. Preparation and properties of KMnO4  and K2Cr2O7
• Coordination Compounds :- Structure and stereoisomerism, importance of coordination compounds (in qualitative analysis, extraction of metals and biological system
• Haloalkanes and Haloarenes :- Uses and environmental effects of -dichloromethane, trichloromethane, tetrachloromethane, iodoform, freons, DDT.
• Alcohols, Phenols and Ethers :- Uses with special reference to methanol and ethanol.
• Amines  :- Diazonium salts: Preparation, chemical reactions and importance in synthetic organic chemistry.
• Biomolecules :- Oligosaccharides  (sucrose, lactose, maltose), polysaccharides (starch, cellulose, glycogen), importance of carbohydrates. Vitamins– classification and functions. Enzymes. Hormones - Elementary idea excluding structure.
• Polymers :- Entire chapter
• Chemistry in Everydaylife :- Entire chapter

If you want to know the JEE Mains, I'm providing you a link that will help you :-

https://engineering.careers360.com/articles/jee-main-chemistry-syllabus

If you want to know the NEET Syllabus then here is the link:-

https://medicine.careers360.com/articles/neet-syllabus

Please mention the full detail in question like board and class, so we can give you the correct and exact information. I hope you understand.

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