Q62.The probability of selecting integers a ∈[−5, 30] such that x2 + 2 (a + 4) x −5a + 64 > 0 , for all x ∈R, is: (1) 7 (2) 2 36 9 (3) 1 (4) 1 6 4 JEE Main 2021 (20 Jul Shift 1) JEE Main Previous Year Paper
What This Question Tests
This question requires knowledge of the structure of semicarbazone, formed by the reaction of acetone with semicarbazide, and then counting the number of nitrogen atoms in the resulting molecule.
Concepts Tested
📚 NCERT Sections This Tests
8.5 — Draw Structures Of The Following Derivatives.
Chemistry Class 12 · Chapter 8
8.5 Draw structures of the following derivatives. (i) The 2,4-dinitrophenylhydrazone of benzaldehyde (ii) Cyclopropanone oxime (iii) Acetaldehydedimethylacetal (iv) The semicarbazone of cyclobutanone (v) The ethylene ketal of hexan-3-one (vi) The methyl hemiacetal of formaldehyde 255 Aldehydes, Ketones and Carboxylic Acids Reprint 2025-26
8.17 — Complete Each Synthesis By Giving Missing Starting Material, Reagent Or Products
Chemistry Class 12 · Chapter 8
8.17 Complete each synthesis by giving missing starting material, reagent or products
8.1 — What Is Meant By The Following Terms ? Give An Example Of The Reaction In
Chemistry Class 12 · Chapter 8
8.1 What is meant by the following terms ? Give an example of the reaction in each case. (i) Cyanohydrin (ii) Acetal (iii) Semicarbazone (iv) Aldol (v) Hemiacetal (vi) Oxime (vii) Ketal (vii) Imine (ix) 2,4-DNP-derivative (x) Schiff’s base
📋 Question Details
- Chapter
- Nitrogen Compounds
- Topic
- Derivatives of aldehydes/ketones, Semicarbazone formation
- Year
- 2021
- Shift
- 20 Jul Shift 1
- Q Number
- Q62
- Type
- Numerical
- NCERT Ref
- Class 12 Chemistry Ch 12: Aldehydes, Ketones and Carboxylic Acids
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