Class 12 Chemistry Notes Chapter 17 (Blue Print of Sample Question Paper) – Examplar Problems Book

Detailed Notes with MCQs of Chapter 17 of your NCERT Exemplar book for Chemistry. This chapter, titled 'Blue Print of Sample Question Paper', isn't about specific chemical reactions or concepts, but it's incredibly important for your exam preparation strategy. Think of it as the architectural plan for your question paper. Understanding this blueprint helps you prepare smartly, focusing your efforts where they matter most.

Understanding the Purpose and Components of a Blueprint

A blueprint for a question paper serves several key purposes:

1. Ensures Balanced Coverage: It helps the paper setter cover the entire syllabus appropriately, assigning weightage to different units or chapters.
2. Sets Difficulty Level: It outlines the distribution of marks across easy, average, and difficult questions.
3. Specifies Question Types: It details how many questions of each type (MCQ, Very Short Answer, Short Answer, Long Answer, Case-Based) will be included and from which topics.
4. Assesses Different Skills: It ensures the paper tests various cognitive abilities – Knowledge, Understanding, Application, and Higher Order Thinking Skills (HOTS).

Key Elements Typically Found in the Blueprint (As exemplified in Chapter 17):

Let's break down the typical grid or table you'll find in this chapter:

1. Content Units/Chapters: The syllabus is divided into major units (e.g., Solutions, Electrochemistry, Chemical Kinetics, d- and f-Block Elements, Coordination Compounds, Haloalkanes and Haloarenes, Alcohols, Phenols and Ethers, Aldehydes, Ketones and Carboxylic Acids, Amines, Biomolecules).
2. Weightage to Content (Marks): Each unit is assigned a specific number of marks in the overall paper. This tells you the relative importance of each unit. For example, you might see that Organic Chemistry units collectively hold a significant chunk of marks.
3. Weightage to Form of Questions: The blueprint shows how the total marks are distributed among different types of questions:
   • MCQ (Multiple Choice Questions): Typically 1 mark each, testing recall, basic understanding, or simple application.
   • VSA (Very Short Answer): Often 1 or 2 marks, requiring brief, specific answers (definitions, simple reasons, naming).
   • SA-I (Short Answer Type I): Usually 2 or 3 marks, needing slightly more explanation, simple calculations, or reasoning.
   • SA-II (Short Answer Type II): Often 3 or 4 marks, requiring more detailed explanations, derivations, multi-step calculations, or comparisons.
   • LA (Long Answer): Typically 5 marks, demanding comprehensive answers, detailed mechanisms, multi-part numerical problems, or elaborate descriptions/comparisons.
   • CBQ (Case-Based Questions): Often 4 or 5 marks each, presenting a passage/data/scenario followed by sub-questions testing interpretation and application.
4. Weightage to Objectives (Cognitive Levels): Marks are also often categorized by the skill being tested:
   • K (Knowledge): Recalling facts, terms, definitions, formulas (e.g., "Define molarity," "State Faraday's first law").
   • U (Understanding): Comprehending concepts, interpreting data, explaining principles (e.g., "Explain why boiling point of alcohol is higher than ether," "Interpret a rate law").
   • A (Application): Using knowledge in new situations, solving numerical problems, applying laws or theories (e.g., Calculating cell potential, predicting reaction products).
   • HOTS (Higher Order Thinking Skills) / S (Skill): Analyzing, evaluating, synthesizing, creating, critical thinking (e.g., Designing a reaction sequence, justifying a complex trend, evaluating different processes).
5. Scheme of Options: The blueprint indicates where internal choices will be provided (usually within SA or LA sections), allowing you to choose which question to attempt.
6. Difficulty Level Summary: Often, a summary indicates the percentage of marks allocated to Easy, Average, and Difficult questions.

How to Use the Blueprint for Strategic Preparation:

1. Identify High-Weightage Areas: Look at the marks allotted to each unit. Focus more study time on units carrying higher marks, but don't neglect lower-weightage ones entirely.
2. Practice Diverse Question Types: If a unit frequently features Long Answer questions (like perhaps Organic conversions or major concepts in Physical Chemistry), practice writing detailed answers. If it's mostly MCQs or VSAs (like maybe some aspects of d-block or Biomolecules), focus on precise facts and definitions.
3. Develop Required Skills:
   • For Knowledge, use flashcards, summaries, and active recall.
   • For Understanding, explain concepts in your own words, draw diagrams, and teach them to someone else.
   • For Application, solve a wide variety of numerical problems and practice reaction mechanisms/conversions extensively.
   • For HOTS, tackle challenging problems from exemplars or previous years' papers that require linking multiple concepts or deeper analysis.
4. Time Management: Use the blueprint's structure (number and type of questions) to practice mock tests under timed conditions. Learn how much time you can afford for each question type.
5. Analyze the Sample Paper: Chapter 17 usually includes a sample question paper based on the blueprint. Solve this paper diligently. It gives you the best feel for the actual exam pattern, language, and difficulty level.

In essence, the blueprint in Chapter 17 is your guide to navigating the examination. It tells you what to study (units), how much importance to give it (marks), and how it might be asked (question types and cognitive level). Use it wisely!

Multiple Choice Questions (MCQs) for Practice

Here are 10 MCQs reflecting the kind of questions you might encounter, covering various topics from your Class 12 Chemistry syllabus:

1. Which of the following exhibits the highest osmotic pressure at a given temperature?
   (a) 0.1 M Urea
   (b) 0.1 M Glucose
   (c) 0.1 M BaCl₂
   (d) 0.1 M NaCl

2. For the reaction A → B, the rate of reaction becomes twenty-seven times when the concentration of A is increased three times. What is the order of the reaction?
   (a) 1
   (b) 2
   (c) 3
   (d) 0

3. The standard electrode potential (E°) values of Al³⁺/Al, Ag⁺/Ag, K⁺/K and Cr³⁺/Cr are -1.66 V, 0.80 V, -2.93 V and -0.74 V, respectively. The correct decreasing order of reducing power of the metal is:
   (a) K > Al > Cr > Ag
   (b) Al > K > Ag > Cr
   (c) Ag > Cr > Al > K
   (d) K > Al > Ag > Cr

4. Which of the following lanthanoid ions is diamagnetic? (Atomic numbers: Ce=58, Sm=62, Eu=63, Yb=70)
   (a) Ce²⁺
   (b) Sm²⁺
   (c) Eu²⁺
   (d) Yb²⁺

5. The IUPAC name for the complex [Co(NO₂)(NH₃)₅]Cl₂ is:
   (a) Pentaamminenitrito-N-cobalt(II) chloride
   (b) Pentaamminenitrito-N-cobalt(III) chloride
   (c) Nitrito-N-pentaamminecobalt(III) chloride
   (d) Pentaamminecobalt(III) nitrito chloride

6. Which reagent will you use for the following reaction?
   CH₃CH₂CH₂CH₃ → CH₃CH₂CH₂Cl + CH₃CH₂CHClCH₃
   (a) Cl₂/UV light
   (b) NaCl + H₂SO₄
   (c) Cl₂ gas in dark
   (d) Cl₂ gas in the presence of iron in dark

7. Identify the product Z in the series:
   CH₃CN --(Na/C₂H₅OH)--> X --(HNO₂)--> Y --(K₂Cr₂O₇/H⁺)--> Z
   (a) CH₃COOH
   (b) CH₃CH₂NHOH
   (c) CH₃CONH₂
   (d) CH₃CHO

8. Which of the following is the most reactive towards nucleophilic addition reactions?
   (a) CH₃CHO
   (b) CH₃COCH₃
   (c) HCHO
   (d) C₆H₅CHO

9. Which vitamin is essential for the coagulation of blood?
   (a) Vitamin A
   (b) Vitamin C
   (c) Vitamin K
   (d) Vitamin D

10. Aniline reacts with bromine water at room temperature to give:
    (a) o-Bromoaniline
    (b) p-Bromoaniline
    (c) A mixture of o- and p-bromoaniline
    (d) 2,4,6-Tribromoaniline

Answers to MCQs:

1. (c) BaCl₂ (Highest van't Hoff factor, i ≈ 3)
2. (c) 3 (Rate ∝ [A]ⁿ; 27 = (3)ⁿ => n=3)
3. (a) K > Al > Cr > Ag (More negative E° means stronger reducing agent)
4. (d) Yb²⁺ (Electronic configuration [Xe] 4f¹⁴, fully filled f-orbital)
5. (b) Pentaamminenitrito-N-cobalt(III) chloride (Correct naming conventions for coordination compounds)
6. (a) Cl₂/UV light (Free radical halogenation of alkanes)
7. (a) CH₃COOH (CH₃CN → CH₃CH₂NH₂ (X) → CH₃CH₂OH (Y) → CH₃COOH (Z))
8. (c) HCHO (Least steric hindrance and electron-donating effect)
9. (c) Vitamin K
10. (d) 2,4,6-Tribromoaniline (Aniline is highly activating, leading to polysubstitution)

Keep practicing and use the blueprint to guide your studies effectively!