CBSE Class 12 Chemistry Sample Paper 2021 Released: Download Now

CBSE Class 12 Chemistry Sample Paper 2021 along with CBSE Class 12 Chemistry Marking Scheme 2021 is available here for download in PDF format. Students preparing for CBSE 12th Chemistry Board Exam 2021 are advised to download these resources and take a close look to check the new exam pattern, marking scheme and the difficulty level.

Also Read: Deleted CBSE Class 12 Syllabus 2020-21: Applicable for CBSE Academic Session 2020-21!

CBSE Class 12 Sample Paper 2021 for All Subjects

CBSE Class 12 Chemistry Sample Paper 2021:

MM:70 Time: 3 Hours

General Instructions:

Read the following instructions carefully.

a) There are 33 questions in this question paper. All questions are compulsory.

b) Section A: Q. No. 1 to 16 are objective type questions. Q. No. 1 and 2 are passage based questions carrying 4 marks each while Q. No. 3 to 16 carry 1 mark each.

c) Section B: Q. No. 17 to 25 are short answer questions and carry 2 marks each.

d) Section C: Q. No. 26 to 30 are short answer questions and carry 3 marks each.

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e) Section D: Q. No. 31 to 33 are long answer questions carrying 5 marks each.

f) There is no overall choice. However, internal choices have been provided.

g) Use of calculators and log tables is not permitted.

SECTION A (OBJECTIVE TYPE)

1. Read the passage given below and answer the following questions: (1x4=4)

An efficient, aerobic catalytic system for the transformation of alcohols into carbonyl compounds

under mild conditions, copper-based catalyst has been discovered. This copper-based catalytic

system utilizes oxygen or air as the ultimate, stoichiometric oxidant, producing water as the only

by-product 

A wide range of primary, secondary, allylic, and benzylic alcohols can be smoothly oxidized to

the corresponding aldehydes or ketones in good to excellent yields. Air can be conveniently used instead of oxygen without affecting the efficiency of the process. However, the use of air requires slightly longer reaction times. This process is not only economically viable and applicable to large-scale reactions, but it is also environmentally friendly.

(Reference:Ohkuma, T., Ooka, H., Ikariya, T., & Noyori, R. (1995). Preferential hydrogenation of

aldehydes and ketones. Journal of the American Chemical Society, 117(41), 10417-10418.)

The following questions are multiple choice questions. Choose the most appropriate answer:

(i)The Copper based catalyst mention in the study above can be used to convert:

a) propanol to propanonic acid

b) propanone to propanoic acid

c) propanone to propan-2-ol

d) propan-2-ol to propanone

(ii) The carbonyl compound formed when ethanol gets oxidised using this copper-based catalyst can also be obtained by ozonolysis of:

a) But-1-ene

b) But-2-ene

c) Ethene

d) Pent-1-ene

OR

Which of the following is a secondary allylic alcohol?

a) But-3-en-2-ol

b) But-2-en-2-ol

c) Prop-2-enol

d) Butan-2-ol

(iii) Benzyl alcohol on treatment with this copper-based catalyst gives a compound ‘A’ which on reaction with KOH gives compounds ‘B’ and ‘C’. Compound ‘B’ on oxidation with

KMnO4- KOH gives compound ‘C’. Compounds ‘A’, ‘B’ and ‘C’ respectively are :

a) Benzaldehyde, Benzyl alcohol, potassium salt of Benzoic acid

b) Benzaldehyde, potassium salt of Benzoic acid, Benzyl alcohol

c) Benzaldehyde, Benzoic acid, Benzyl alcohol

d) Benzoic acid, Benzyl alcohol, Benzaldehyde

(iv) An organic compound ‘X’ with molecular formula C3H8O on reaction with this

copper based catalyst gives compound ‘Y’ which reduces Tollen’s reagent. ‘X’ on

reaction with sodium metal gives ‘Z’ . What is the product of reaction of ‘Z’ with 2-

chloro-2-methylpropane?

a) CH3CH2CH2OC(CH3)3

b) CH3CH2OC(CH3)3

c) CH2=C(CH3)2

d) CH3CH2CH=C(CH3)2 

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For all he questions and answers, download the CBSE Class 12 Chemistry Sample Paper 2021 and CBSE Class 12 Chemistry Marking Scheme 2021 from the links given below

Download CBSE Class 12 Chemistry Sample Paper 2021

Download CBSE Class 12 Chemistry Marking Scheme 2021

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