| After months of stringent exam preparations, you are all set to appear for CBSE Class 12 Chemistry Board Exam, which will be conducted on 12th March. The subject Chemistry is considered to be difficult as it involves a lot of understanding and application of equations, formulae, numericals and more. Students do put their best foot forward to grab a perfect score, still they lose marks as they commit some silliest mistakes while giving the exam. Undoubtedly, hard work and right preparation are necessary to perform well, it is equally important how you act in the examination hall and write the exam. |   |
Often the students are so anxious while writing the exam that they do mistakes in all the three sections of CBSE Class 12 Chemistry paper - Physical, Organic & Inorganic Chemistry. Although these mistakes have nothing to do with the knowledge of the subject, but if not paid good attention can lead to loss of marks. Let us find out these mistakes, to avoid committing these mistakes.
Physical Chemistry
- In a numerical question, half or one mark is assigned for writing the formula, substituting values in the formula, perfect numerical value and proper unit. Students usually commit mistakes in these areas. Be attentive, you need to check the compatibility of all the units, either SI or CGS system. Students also tend to make mistake of writing the numerical values and the final answer without proper units
- In laws-based questions, students generally rephraise the statements or only write the mathematical expression. However, students need to be aware of the fact that marks are only allotted to the statement of law. Therefore, they have to write all the laws as it is stated.
- In graph-based questions, students often plot the graph, but they forgot to write the variables which results in losing marks. They need to write the variables along both the axes with proper units and mention the slope and intercept. Be cautious.
- For Reason based questions students are required to take care of the word limit of the question. If the question is of 1 mark, then write answer to the point about whatever is asked in the question. For example, if only definition is asked then there is no need to give examples. If two consequences are asked, then write only two. If one example is asked, then do not give two examples. Do not try to write extra information, try to save time for other questions.
Organic Chemistry
- Students often make mistakes when writing the IUPAC nomenclature of the compound in context. They mistakenly write -al suffix instead of -ol or their handwriting appear confusing between -al and -ol. Many students also make mistakes in identifying the substituted alkyl group. There should not be any spelling mistake while writing the IUPAC name of the organic compound. You should go through the rules and practice thoroughly from study resources that give clear and vivid conceptual information. To make sure you understand concepts correctly, read from MTG’s CBSE Champion Chemistry. This book offers everything that will convert your hard efforts into grand success.
2.Usually students make a mistake of not writing which compound is responding to the test though the observation is given. For example, writing the name of the test, like iodoform test and not writing the reagent i.e. NaOH and I2. This has to be rectified.
3. Be attentive while writing the answer as it must correspond to the question. Students need to pay attention to whether name or structure/formula is asked for in the question.
4. Students also tend to forget to mention the reagents involved in the reaction.
5. Another mistake lies in not mentioning and highlighting all the steps, for example,
- arrows showing electron transfer.
- types of reactions involved in the mechanism (eg: nucleophilic substitution).
Inorganic Chemistry
- While representing the structure of a substance, students make certain mistakes like:
- Forget to draw ‘proper structure with all elements, bonds and lone pairs of electrons'.
- When question specifies to mention about shape/geometry and hybridisation,then mention them properly. Generally students only draw the structures and do not write its shape/geometry and hybridisation.
- While writing the equation of a chemical reaction, the balancing of the equation is a must. However, most students tend to
- Not balance the chemical reaction by mentioning the physical states of reactants and products and the conditions above the arrow head.
- Write the equation when asked about observation of a reaction.
- In reason-based questions, students forget to give the cause of a phenomenon when asked to reason it. If the consequence is due to a phenomenon such as Lanthanide contraction, or inert pair effect, these terms must be mentioned and highlighted.
- Students also lose marks when they forget to mention the Principle when explaining a process. So, never forget to mention the Principles involved behind the process.
Final Advice:
The final advice before you step into the examination hall, write answer within the word limit and highlight all the keywords. The art of giving proper answers in CBSE Class 12 Chemistry Exam can easily be understood with the help of marking scheme issued by CBSE board . You must go through it! As few days are now left for the exam, revision by practising from the latest CBSE sample papers & previous year papers is extremely important. Practicing sample paper will give you the idea about changes in latest examination pattern whereas previous year papers will give you the idea about the level of questions and important concepts which are frequently asked in CBSE board exam, every year.RELATED ARTICLE: CBSE Class 12th Boards Are Approaching, Know How To Boost Your Revision
