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Alok Bariyar, Hindustan Times
New Delhi, January 22, 2013
Piles of notes, loads of textbooks and late night studies! Yes, board exams have reached your doorsteps. The last few months before the examination are very crucial and require ‘smart and quick study’. As a combination of atoms makes molecules, similarly a combination of efforts makes success. You must have a sound strategy to excel and be among the toppers. Even if your mock board exam scores to date have been in the lower bracket, you can always improve by 20-25% by following a disciplined revision strategy.

Pounce on the syllabus, after all there are only 16-odd chapters and a limited number of FAQs which form a major chunk of your 70-marks question paper. Divide your syllabus into smaller parts as given below:

1 Part one comprises physical chemistry chapters like solution, solid state, electrochemistry, chemical kinetics and surface chemistry. Since it is a formula-based segment, numericals and sometimes small derivations are asked in this part. The final answer of units should be taken care of. Always start the answer by writing the standard notation followed by substitution of values with units. Numericals carry stepwise marking, even if you write the general formula and substitute the values, you manage to score half of the total marks.

2 Part two includes organic chemistry chapters – halogen-containing compounds, alcohol, phenol, ether, aldehydes, ketones and carboxylic acid, and amines. This part is based on concept and applications. Questions are mainly in the form of conversions, name reactions, mechanism of organic reactions and loop reactions.

3 Part three contains inorganic chemistry chapters such as P-block elements, D- and F-block elements, coordination compounds and principles of extraction. It has three categories – structure-based (for example, draw the structure of XeOF4), reasoning-based (for example, arrange certain compounds in order of acid/base strength etc) and reaction-based (for example, what happens when NCl3 is hydrolysed). In both part two and three, always support the answers with structures, examples, equations and graphs even if the question does not ask for it and all equations must be balanced. A reaction, which is not balanced, is not an equation. Take the following example

Q: Complete the following chemical reaction equations:

(i) P4 + SO2Cl2 ? Model Ans: (i) P4 + 10 SO2Cl2 ? 4 PCl5 + 10 SO2 (CBSE 2010 Set 3, Q 30).

Similarly, reasoning questions carry one mark each and demand precise answers.

4 Part four consists of biomolecules, polymers, and chemistry in everyday life. This part requires thorough reading of the NCERT textbook. Questions are fairly straight-from-the-book type. For example, distinguish between fibrous and globular protein etc or draw the structures of the monomers of the following polymers: (i) Teflon (ii) Polythene (CBSE 2009 Set 1, Q 18, Chapter - Polymers).

Remember that revision will be completed only after writing two or three small tests on these topics; get them evaluated contentwise and writing-skillwise.

Other important things that you should keep in mind while writing the exam are: read the question paper thoroughly in the initial 15 minutes and mark the questions you are confident in answering. Write the answers to all questions of one section at one place and in sequence, draw lines for rough work on the right-hand side. This would minimise the chances of errors in noting down the answer (especially the numeric values) from rough calculations. Underline the keywords in the answer.

Topper talk

Karan Kampani
Bal Bharti, Pitampura

Scored 95/100 in his Class 12 chemistry board exam

Practise a lot of sample papers

I wasn’t always an academically serious student because of my involvement in co-curricular activities. I got serious after October when I had my half-yearly examination result in my hand. Practise a lot of sample papers. Clarity of concepts is extremely important to be able to apply it

The author is head, department of chemistry, HT Studymate, tuition centres for Class 9 to Class 12. A former nuclear scientist, he has more than 14 years of experience in teaching and mentoring students.