Acidity: Carboxylic Acids versus alcohols

    ❒ Carboxylic acids are weak acids, typically having pKa values in the range of 3–5. Alcohols, by comparison, have pKa values in the range of 15–18, and essentially do not give up a proton unless exposed to a very strong base. ❒ To understand the reasons for this difference, let’s consider acetic acid …

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The Kinetic Molecular Theory of Gases

  Introduction ❒The gas laws help us to predict the behavior of gases, but they do not explain what happens at the molecular level to cause the changes we observe in the macroscopic world. For example, why does a gas expand on heating? ❒ In the nineteenth century, a number …

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Hybridization and Shapes of Molecules

  ❒ In the previous subject we talk about the concept of Hybridization and the types of Hybridization, but in this subject we will talk about Hybridization and Shapes of Molecules. ❒ Diatomic molecules must all be invariably linear but tri-and tetra-atomic molecules have several possible geometrical structures. In this …

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The Molar Mass of a Gaseous Substance

  The Molar Mass of a Gaseous Substance ❒ From what we have seen so far, you may have the impression that the molar mass of a substance is found by examining its formula and summing the molar masses of its component atoms. However, this procedure works only if the …

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Concept Of Hybridization

     While formation of simple molecules could be explained adequately by overlap of atomic orbitals, the formation of molecules of Be, B and C present problems of greater magnitude having no solution with the previous theory. To explain fully the tendency of these atoms to form bonds and the …

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Thermodynamics in Organic Chemistry

    ❒ For a reaction to be practical, the equilibrium must favor the products, and the reaction rate must be fast enough to form them in a reasonable time. These two conditions depend on the thermodynamics and the kinetics of a reaction, respectively. ❒Thermodynamics describes energy and equilibrium. How …

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Orbital Representation Of Molecules

  (a) Formation of H2molecule   ❒Each hydrogen atom has one electron in 1s-orbital. ❒Two such atoms join to form a molecule of hydrogen. ❒In this case s–s overlapping between two 1s-orbitals of hydrogen atoms taken place resulting in the formation of hydrogen molecule. ❒There exists a sigma bond between …

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Solved problems on Ideal gas law

    Example (1): Calculate the volume of a sample of gas originally occupying 908 mL at 717 torr and 20 oC after its temperature and pressure are changed to 72 oC and 1.07 atm. Solution Again, tabulating the data is a good idea. The volume can be stated in …

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The Ideal Gas Equation

  The Ideal Gas Equation ❒ Let us summarize the gas laws we have discussed so far:     ❒ We can combine all three expressions to form a single master equation for the behavior of gases:.     This Equation is called the ideal gas equation where R , the proportionality …

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Lewis Acids and Bases

Lewis Acids and Bases ❒ In 1923 G. N. Lewis proposed a theory that significantly broadened the understanding of acids and bases. ❒ As we go along we shall find that an understanding of Lewis acid– base theory is exceedingly helpful to understanding a variety of organic reactions. ❒ Lewis …

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The Volume-Amount Relationship: Avogadro’s Law

  The Volume-Amount Relationship: Avogadro’s Law ❒ The work of the Italian scientist Amedeo Avogadro complemented the studies of Boyle, Charles, and Gay-Lussac. ❒ In 1811 Avogadro published a hypothesis stating that at the same temperature and pressure, equal volumes of different gases contain the same number of molecules (or atoms …

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