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bookmark42.com My Library Physics Vol 1 Organic Chemistry Calculus — HC Verma Biology NCERT CHAPTERS Ch 5 — Aromatic Reactions Ch 6 — Alcohols Ch 7 — Aldehydes Ch 8 — Carboxylic Acids Page 42 / 218 Chapter 5: Aromatic Substitution Electrophilic aromatic substitution (EAS) is one of the most important reactions in organic chemistry. In EAS, an electrophile replaces a hydrogen atom on the ring. Definition: A sigma complex is the intermediate formed when the electrophile bonds to a carbon on the ring, temporarily disrupting the aromatic pi system. Example: Friedel-Crafts alkylation of benzene with CH₃Cl proceeds via a carbocation intermediate, yielding toluene as the primary product. The Lewis acid catalyst AlCl₃ generates the electrophile in situ. Confused: Why does the sigma complex lose aromaticity but not stability? Need to revisit MO theory for this. The reaction rate is highly dependent on the nature of substituents already present on the ring. Electron- donating groups activate the ring toward further EAS. Page 42 of 218 AI AI Buddy Why does the sigma complex lose aromaticity but not stability? Great question! The sigma complex temporarily loses aromaticity because the pi electron cloud is disrupted. But it remains relatively stable due to charge delocalisation across the remaining 4 carbon atoms. Saved to highlight Explain MO theory basics → Compare with Wheland int. → Ask about this highlight...
My Books 📘 Physics Vol 1 📗 Organic Chem 📕 Calculus Chapters ▸ Ch 3 — Forces Ch 4 — Energy Ch 5 — Waves Chapter 3: Forces and Motion Newton's first law states that an object at rest stays at rest unless acted upon by an external force. This is also known as the law of inertia. The second law relates force, mass, and acceleration: F = ma. A greater force produces a greater acceleration for a given mass. The third law: every action has an equal and opposite reaction. When you push a wall, the wall pushes back on you with equal force. Page 42 of 218

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Organic Chemistry — Ch 5 Electrophilic aromatic substitution is a key reaction in organic chemistry where an electrophile replaces an atom on the aromatic ring. The mechanism involves formation of a sigma complex intermediate. The rate of reaction depends on the electron density of the aromatic ring. AI Buddy You asked: What is a sigma complex? AI says: It's a temporary structure where the electrophile bonds to the ring, breaking its aromaticity briefly. Ask more →

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Chapter 3 Quiz 3 / 10 Q3. What is the primary function of mitochondria? Energy storage in cells ATP production (cellular respiration) Protein synthesis ✓ Correct! Mitochondria are the powerhouse of the cell. Next →

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All Notes (5) Key formula: F = ma Physics Ch 3 · Today Mitosis vs Meiosis Biology Ch 7 · Yesterday Sigma complex defn Chem Ch 5 · 2 days ago Integration rules Calculus Ch 2 · 3d ago Key formula: F = ma Newton's second law — force equals mass times acceleration. Useful for solving projectile motion problems. Remember: • 1 Newton = 1 kg·m/s² • Weight = mass × gravity • Net force = ΣF (vector sum) Physics Chapter 3 Last edited: Today, 2:35 PM

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