The CBSE Class 12 board exams are scheduled between February 15 and April 3, 2018. And students are all set to take the most exciting subject, Chemistry, on Mar 12, 2019. With less than a week left for the Chemistry examination, this is the time for the students to revise and start a selective study.
Most of us know that the CBSE Class 12 Chemistry subject has a huge syllabus and is categorised into three sections, namely, Physical, Inorganic and Organic Chemistry. A total of 15 units were there in this Class 12 Chemistry, which are almost equal in terms of subject knowledge and marks weightage.
After careful consideration of the CBSE previous year papers, we have prepared a list of important topics one need to consider in the last days. Prior to exploring the important topics of the Class 12 Chemistry, students should know the marks allotted for the units in the respective paper. A total of 23 marks are allotted for Units between I and V. At least 19 marks are carried for Units between VI and IX. And 28 marks for Units-X to XVI.
Unit I To III
Unit-I - Solid State
The questions are likely to be asked on the metallic solids in the classification of solids based on different binding forces, numerical problems on the calculation of density of unit cell and electron sea model.
Unit-II - Solutions
Students can expect one mark questions on types of solutions. The other important topics are Henry's law, depression of freezing point, Van't Hoff factor and osmotic pressure.
Unit-III - Electrochemistry
One can expect one mark questions on conductance in electrolytic solutions and Kohlrausch's Law. The Faradays' laws, lead accumulator and standard electrode potential are important.
Unit IV to VI
Unit-IV - Chemical Kinetics
The rate of reaction, concept of collision theory, effect of temperature in activation energy, Arrhenious equation and concept of collision theory are very important.
Unit-V - Surface Chemistry
The adsorption - physisorption and chemisorption are very important along with Tyndall effect and Brownian movement. Students should also focus on types of emulsions.
Unit-VI - Isolation of Elements
The principles and methods of extraction - concentration, oxidation, reduction are very important.
Unit VII to IX
Unit-VII - p-Block Elements
In the Group 15 Elements, the conceptual questions are expected this year from compounds of Nitrogen and preparation properties & uses of Nitrogen. The same goes for Phosphorus as well. The questions on Ozone, Sulphur and Sulphuric acids are expected in the Group 16 Elements. While coming to the Group 17 Elements, compounds of halogens and oxoacids of halogens are crucial.
Unit-VIII - d-Block And f-Block Elements
In the first row transition metals, ionization enthalpy, oxidation states and interstitial compounds are important. Take a close look on the topics related to Lanthanoids and Actinoids.
Unit-IX - Coordination Compounds
Students are advised to revise the coordination number, colour, magnetic properties and shapes thoroughly. The structure and stereo isomerism are also equally important.
Unit X to XII
Unit-X - Haloalkanes and Haloarenes
Read the nomenclature, nature of C-X bond, optical rotation and uses & environmental effects of - dichloromethane, trichloromethane, tetrachloromethane, iodoform, freons and DDT.
Unit-XI - Alcohols, Phenols and Ethers
Read thoroughly the nomenclature, methods of preparation, uses and properties of Alcohols, Phenols and Ethers.
Unit-XII - Aldehydes, Ketones and Carboxylic Acids
Not much important in this unit. However, give special attention to carboxylic acids uses and mechanism of Nucleophilic addition.
Unit XIII to XVI
Unit-XIII - Organic Compounds containing Nitrogen
The Amines methods of preparation is the most important besides identification of primary, secondary and tertiary amines. The chemical reactions and importance in synthetic organic chemistry is also important.
Unit-XIV - Biomolecules
The classification of aldoses and ketoses, denaturations of proteins, classification of vitamins and nucleic acids - DNA and RNA are important.
Unit-XV - Polymers
Give utmost importance to the methods of polymerization, copolymerization and bakelite.
Unit-XVI - Chemistry in Everyday Life
In the chemicals in medicine, focus on antibiotics and antacids. In the chemicals in food, give importance to artificial sweetening agents. However, soaps, detergents and cleansing action are important in the cleansing agents.