CBSE Class 12 Chemistry Boards 2020 Question Paper Solved Set A

Access and download CBSE Class 12 Chemistry Boards 2020 Question Paper Solved Set A, carefully designed as per the latest 2025-26 examination guidelines issued by CBSE, NCERT, and KVS. These Class 12 Chemistry previous year question papers include detailed solutions, helping students to assess their performance and identify and improve key areas before the final exams.

Solved Chemistry Question Papers for Class 12

Practicing these Class 12 Chemistry question papers is the best way to understand the actual exam pattern and marking scheme. By solving these papers under timed conditions, Class 12 students can improve their speed and accuracy. Download the full CBSE Class 12 Chemistry Boards 2020 Question Paper Solved Set A to begin your self-assessment today.

Chemistry Class 12 Question Paper PDF with Solutions

SECTION A
Read the given passage and answer the questions number 1 to 5 that follow :
 
The substitution reaction of alkyl halide mainly occurs by SN1 or SN2 mechanism. Whatever mechanism alkyl halides follow for the substitution reaction to occur, the polarity of the carbon halogen bond is responsible for these substitution reactions. The rate of SN1 reactions are governed by the stability of carbocation whereas for SN2 reactions steric factor is the deciding factor. If the starting material is a chiral compound, we may end up with an inverted product or racemic mixture depending upon the type of mechanism followed by alkyl halide. Cleavage of ethers with HI is also governed by steric factor and stability of carbocation, which indicates that in organic chemistry, these two major factors help us in deciding the kind of product formed.
 
1. Predict the stereochemistry of the product formed if an optically active alkyl halide undergoes substitution reaction by SN1 mechanism.
 
2. Name the instrument used for measuring the angle by which the plane polarised light is rotated.
 
3. Predict the major product formed when 2-Bromopentane reacts with alcoholic KOH.
 
4. Give one use of CHI3.
 
5. Write the structures of the products formed when anisole is treated with HI.
 
Questions number 6 to 10 are one word answers :

6. Identify which liquid will have a higher vapour pressure at 900C if the boiling points of two liquids A and B are 1400C and 1800C, respectively.
 
7. Out of zinc and tin, whose coating is better to protect iron objects ?
 
8. Will the rate constant of the reaction depend upon T if the Eact (activation energy) of the reaction is zero ?
 
9. Give the structure of the monomer of PVC.
 
10. Which structural unit present in a detergent makes it non-biodegradable ?
 
Questions number 11 to 15 are multiple choice questions :
 
11. Out of the following, the strongest base in aqueous solution is
 
(A) Methylamine
 
(B) Dimethylamine
 
(C) Trimethylamine
 
(D) Aniline
 
12. Iodoform test is not given by
 
(A) Ethanol
 
(B) Ethanal
 
(C) Pentan-2-one
 
(D) Pentan-3-one
 
13. Out of the following transition elements, the maximum number of oxidation states are shown by
 
(A) Sc (Z = 21)
 
(B) Cr (Z = 24)
 
(C) Mn (Z = 25)
 
(D) Fe (Z = 26)
 
14. Hardening of leather in tanning industry is based on
 
(A) Electrophoresis
 
(B) Electro-osmosis
 
(C) Mutual coagulation
 
(D) Tyndall effec
Please click on below link to download CBSE Class 12 Chemistry Boards 2020 Question Paper Solved Set A.

CBSE Class 12 Chemistry Boards 2020 Question Paper Solved Set A

To understand the types of questions asked in past examinations, it is very important for Class 12 students to solve the CBSE Class 12 Chemistry Boards 2020 Question Paper Solved Set A provided above. You can easily download these past papers for Class 12 Chemistry in PDF format for the last 10 years. By practicing these actual exam questions you will gain an understanding of the difficulty level and the variety of topics covered over the years. By solving these Previous Year Papers (PYPs) you will understand both descriptive and MCQ questions in your final tests.

Importance of solving CBSE Class 12 Chemistry Boards 2020 Question Paper Solved Set A

Regularly practicing CBSE Class 12 Chemistry Boards 2020 Question Paper Solved Set A is the best way to improve your score in Class 12 Chemistry. These papers will give you details of the marking scheme and the paper structure used by the CBSE. By regularly attempting these under actual exam conditions at home, you can slowly improve your time management skills, which will help you to complete your Chemistry paper within the allowed duration.

Benefits of downloading CBSE Class 12 Question Papers

Having the CBSE Class 12 Chemistry Boards 2020 Question Paper Solved Set A in PDF format allows you to revise key concepts anywhere, even without an internet connection. These sets are a reliable tool to practice numerical problems and understand the correct approach to all types of answers. After solving the questions, you should compare your work with the solutions provided by our teachers. Along with these papers, students should always solve the Class 12 Chemistry Sample Papers and MCQ tests on studiestoday.com for a complete revision.

Where can I download the official PDF for CBSE Class 12 Chemistry Boards 2020 Question Paper Solved Set A?

The CBSE Class 12 Chemistry Boards 2020 Question Paper Solved Set A is available for download on StudiesToday.com. It includes complete set with all sections so that Class 12 students can practice with the exact same paper that came in the CBSE exams.

Are the solutions for CBSE Class 12 Chemistry Boards 2020 Question Paper Solved Set A based on the official CBSE marking scheme?

Yes, the solutions for CBSE Class 12 Chemistry Boards 2020 Question Paper Solved Set A are prepared by subject matter experts as per official marking scheme. Class 12 students will understand the structure of answers and 'step-marks' methodology Chemistry.

How does solving CBSE Class 12 Chemistry Boards 2020 Question Paper Solved Set A help in preparing for the 2026 exams?

Solving previous year papers like CBSE Class 12 Chemistry Boards 2020 Question Paper Solved Set A is important to understand repeat themes and question difficulty levels of Chemistry. It helps Class 12 students to test their time management skills too.

Can I access CBSE Class 12 Chemistry Boards 2020 Question Paper Solved Set A in different languages?

Yes, where applicable, CBSE Class 12 Chemistry Boards 2020 Question Paper Solved Set A is available in both English and Hindi mediums. All students from Class 12 can access Chemistry study material in their preferred language.

Is there a charge to download the CBSE Class 12 Chemistry solved papers?

No, all previous year question papers on StudiesToday, including CBSE Class 12 Chemistry Boards 2020 Question Paper Solved Set A, are provided free of charge in mobile-friendly PDF.