There is Case Study Questions in class 12 Chemistry in session 2020-21. For the first time, the board has introduced the case study questions in the board exam. The first two questions in the board exam question paper will be based on Case Study and Assertion & Reason. The first question will have 5 MCQs out of which students will have to attempt any 4 questions. The second question will carry 5 Assertion & Reason type questions with the choice to attempt any four. Here are the questions based on case study.
Case Study Question 1:
Read the passage given below and answer the following questions:
A mixture of two aromatic compounds (A) and (B) was separated by dissolving in chloroform followed by extraction with aqueous KOH solution. The organic layer containing compound (A), when heated with alcoholic solution of KOH produce C7H5N (C) associated with unpleasant odour.
The following questions are multiple choice question. Choose the most appropriate answer:
(i) What is A?
(d) None of these
The reaction of (A) with alcoholic solution of KOH to produce (C) of unpleasant odour is called
(a) Sandmeyer reaction
(b) Carbylamine reaction
(c) Ullmann reaction
(d) Reimer-Tiemann reaction.
(ii) The alkaline aqueous layer (B) when heated with chloroform and then acidified give a mixture of isomeric compounds of molecular formula C7H6O2. (B) is
(iii) In the chemical reaction, CH3CH2NH2 + CHCl3 +3KOH → (A) + (B) + 3H2O, the compounds (A) and (B) are respectively
(a) C2H5NC and KCl
(b) C2H5CN and KCl
(c) CH3CH2CONH2 and KCl
(d) C2H5NC and K2CO3
(iv) Direct nitration of an aromatic compounds (A) is not feasible because
(a) the reaction cannot be stopped at the mononitration stage
(b) a mixture of o, m and p-nitroaniline is always obtained
(c) nitric acid oxidises most of the aromatic compounds to give oxidation products along with only a small amount of nitrated products
(d) all of the above