CBSE Class 12 Board Exam 2020: Last Minute Revision Tips for Chemistry

The CBSE Class 12 Chemistry board exam 2020 is around the corner. While we’re sure you’ve been revising thoroughly for the paper, we have some last-minute tips to help you stay on top while taking the exam.

Let’s quickly look at the Chemistry topics and how you should approach your revision for CBSE class 12 boards 2020:

Physical Chemistry

Theory and numerical for this section can be covered if you have been revising steadily from your NCERT textbook. While you should be familiar with all subjects in the syllabus, the following are the topics in that appear a lot in the Chemistry paper for this section. Be sure to go through the theory, solved samples, and several practice tests for these subjects.

Solid States:

• Difference between amorphous & crystalline solids
• Density of unit cell (Numerical)
• Types of defects (Frenkel & Schottky)
• Magnetic properties

Solutions

• Definition and application of Henry’s Law
• Raoult’s Law of definition and Dalton’s law
• The condition for ideal solution
• Deviation from ideal behaviour (Graph)
• Colligative properties

Electrochemistry

• Galvanic Cell
• Standard Hygiene Electrode
• Nernst Equation (Numerical)
• Definition of conductance, conductivity and molecular conductance
• Electrolytic cell: construction + diagram
• Faraday’s Law of electrodes
• Fusion cell and its uses
• Corrosion: Cell reaction & prevention

Surface Chemistry

• Physical absorption vs chemical absorption
• Freundlich adsorption isotherm graph
• Homogeneous & Heterogeneous Catalysis
• Shape Selective Catalyst
• Enzyme Catalysis
• Lyophilic vs. Lyophobic Colloid
• Bredig’s Arc Method
• Peptization
• Properties of the colloidal solution

Chemical Kinetics

• The rate of reaction: Expression for average rate of reaction
• Rate Law definition, order of reaction
• Integrated Rate Equation
• Arrhenius Equation
• Collision Theory

Organic Chemistry

This is a scoring section which carries quite high weightage in the paper. Our recommendation would be to get strong with ALL reactions by practising and writing them down multiple times to get comfortable with questions related to Conversions. This will also help in becoming familiar with Name Reactions, as you will then only have to remember the names of some reactions that you have already practised and learned. With IUPAC nomenclature questions sure to come up, our recommendation is to write them down to memorize them better as well.

While all topics are important, here’s our suggestion of must-do topics in case you are low on time.

Haloalkanes & Haloarenes

• SN1 & SN2 (order of reactivity, difference)
• Elimination Reaction (Saytzeff Rule)
• Phosgene Gas

Alcohol, Phenol & Ethers

• Acid Catalysed Hydration Mechanism
• Lucas Test (distinguishing test)
• Grignard Reagents
• Hydroboration-Oxidation

Aldehyde Ketone and Carboxylic Acid

• Hemiacetal/Hemiketal Reaction
• Tollens and Fehlings Test
• Aldol Condensation
• Iodoform Test
• Mechanism of Nucleophilic Addition

Amines

• Order of basicity
• Diazonium Salts
• Hinsberg Test
• Nitration

Inorganic Chemistry

P-block elements are the most important chapter that must be thoroughly revised. Reaction questions are very common so being familiar with them is a must.

The best way to approach would be to write down all the reactions and review them repeatedly. This is true for d- and f-block elements as well as Metallurgy and Coordination Compound.

The Chemistry paper is quite lengthy, but if you have been practicing the syllabus by writing down the reactions and solving sample papers, then you will have developed the speed needed to finish the paper on time. Remember to attempt all questions, because you can get half-marks if your steps are correct. Lastly, be neat and tidy when attempting questions, and be sure to revise your answers before submitting them. Best of luck!