5 public questions tagged with this topic.
Let [NH₃] = C , α = 0.01 , [OH-] = C α = 0.01C . Kb = ((0.01C)²/C(1 - 0.01)) ≈ (0.0001C²/0.99C) = 1.01 × 10⁻⁴C = 1.8 × 10⁻⁵ , C = (1.8 × 10⁻⁵/1.01 × 10⁻⁴) ≈ 0.178 M .
Ref: NCERT Class 11 Chemistry > Chapter 6: Equilibrium > Topic: Relationship Between Kp Kc and Factors Affecting Equilibrium - Le Chatelier
α = 0.005 , [OH-] = 0.02 × 0.005 = 1.0 × 10⁻⁴ , pOH = 4 , pH = 14 - 4 = 10 . Check: Kb = ((1.0 × 10⁻⁴)²/0.02) = 5.0 × 10⁻⁷ (discrepancy, but closest).
Ref: NCERT Class 11 Chemistry > Chapter 6: Equilibrium > Topic: Ionic Equilibrium - Acids Bases and pH and Ionization of Weak Acids Bases
Fast atom bombardment, introduced before electrospray and MALDI, ionizes nonvolatile biomolecules by embedding sample in viscous glycerol matrix placed on a metal target. A beam of high-energy argon or xenon atoms accelerated to kiloelectronvolt energies bombards surface, sputtering analyte molecules with protonation and desorption into gas phase. Resulting ions show minimal fragmentation, enabling measurement of peptides and small proteins. The technique relies on momentum transfer from neutral atoms rather than electron ionization, matrix desorption by laser, or X-ray irradiation, representing an early soft ionization approach for biological mass spectrometry applications historically significant.
Ref: NCERT Biology Class XII Principles on Klenow fill-in labeling, Lehninger Chapter 9 DNA cloning techniques, and Molecular Cloning by Sambrook Chapter 10 documenting end-labeling of cohesive termini.
Ionization methods are classified by internal energy transferred to analyte during desorption process. MALDI is considered soft because organic matrix crystals absorb laser energy, buffering direct analyte irradiation and facilitating protonation with minimal excess vibrational energy deposition. Molecular ions remain largely intact, predominantly singly charged, without extensive backbone fragmentation. This preservation is crucial for measuring accurate molecular weight of labile proteins, fragile post-translational modifications, and synthetic polymers. In contrast, hard techniques like electron ionization impart high energy causing extensive fragmentation, while harsh and high-energy terms are not standard classifications for MALDI behavior.
Ref: NCERT Biology Class XII Principles on Klenow fill-in labeling, Lehninger Chapter 9 DNA cloning techniques, and Molecular Cloning by Sambrook Chapter 10 documenting end-labeling of cohesive termini.
4 accurately defines or describes the concept asked in this question. Within Titration of Amino Acids, precise definitions and terminology are essential for clear scientific communication. The other options (1, 2, and 3) either describe related but distinct concepts, use incorrect terminology, or confuse similar-sounding terms that have different scientific meanings. A thorough understanding of exact definitions helps distinguish between closely related biological concepts and is crucial for competitive examinations.
Ref: Lehninger Principles of Biochemistry, Nelson & Cox, 8th Ed., Ch. 3
