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Carbocations: Factors affecting their Stability

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A carbocation is a species where a carbon atom bonds to three carbon atoms and has a positive charge. Carbocations are electron deficient species and therefore very reactive and unstable . Anything which donates electron density to the electron-deficient center will help to stabilize them. Factors that stabilize them are the following:  Neighboring carbon atoms (inductive effect) Neighboring carbon-carbon multiple bonds (resonance effect) Neighboring atoms with lone pairs (resonance effect) How carbocations are stabilized by neighboring carbons atoms? The stability of carbocations decreases as the number of carbons attached to the C+ decreases. That means that tertiary carbocations are more stable than secondary that in turn are more stable than primary (Fig. 1). Fig. 1: Carbocation stability increases as methyl substitution increases around the electron deficient carbon C+. The methyl groups (-CH 3 ) are electron donating and therefore stabilize the positive charge (inductive ...
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Standard Enthalpies of Formation of Organic Compounds

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CHEMISTRY NET - INTRODUCTION - LIST OF TOPICS

Chemistry Net - Introduction - Table of Contents CHEMISTRY NET Analytical Chemistry Biological Chemistry Inorganic Chemistry Organic Chemistry Physical & Theoretical Chemistry Chemical News & Interesting / Chem. Data Chemistry is the understanding, the definition and the description of the structure and the behavior of matter, the matter that surrounds us and the matter we are consisting off. It is our history, our life and our future. It is sometimes called the central science because of its role in connecting the other physical sciences (physics, astronomy, earth sciences) with the life sciences (biology, medicine) and engineering. There are many approaches to studying this fascinating science but for convenience and historical reasons has been divided it into five fields: analytical , biological , inorganic , organic and physical chemistry. Chemistry is a challenging subject to teach and even more challenging to learn. This si...
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