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Use concentrated sulfuric or phosphoric acid, remove low-boiling alkene as it forms to shift the equilibrium, and increase the yield of the reaction. Carbocation intermediate: 3º alcohols react faster than 2º. Primary alcohols are the least reactive. Rearrangements are common. Reaction obeys Zaitsev’s rule.

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Brønsted-Lowry bases are H+ acceptors any material that has atoms with lone pairs can potentially be a Brønsted-Lowry base because of the molecular structure, often one atom in the molecule is more willing to accept H+ transfer than others NH3(aq) is basic because NH3 accepts an H+ from H2O, forming OH–(aq) water acts as acid, donating H+

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Strength of the nucleophile determines order: Strong nucleophiles or bases promote bimolecular reactions. Primary halide usually undergo SN2. Tertiary halide mixture of SN1, E1 or E2. They cannot undergo SN2. High temperature favors elimination. Bulky bases favor elimination.

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when the solute-to-solvent attractions are weaker than the sum of the solute-to-solute and solvent-to-solvent attractions, the solution will only form if the energy difference is small enough to be overcome by the entropy

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Diastereomers have different physical properties, so they can be easily separated. Enantiomers differ only in reaction with other chiral molecules and the direction in which polarized light is rotated. Enantiomers are difficult to separate. Convert enantiomers into diastereomers to be able to separate them.

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A strong base can abstract a proton from tribromomethane (CHBr3) to give an inductively stabilized carbanion. This carbanion expels bromide ion to give dibromocarbene. The carbon atom is sp2 hybridized with trigonal geometry. A carbene has both a lone pair of electrons and an empty p orbital, so it can react as a nucleophile or as an electroph...

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(c) The trans isomer is more stable. The most stable conformation of the trans isomer is diequatorial and therefore about 7.6 kJ/mol (1.8 kcal/mol) lower in energy than either conformation of the cis isomer, each having one methyl axial and one equatorial. Remember that cis and trans are distinct isomers and cannot interconvert.

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Alkanes: Single bonds between the carbons; all carbons are sp3. Cycloalkanes: sp3 carbons form a ring. Alkenes: Double bonds are present in the molecule; sp2 carbons. Cycloalkenes: Double bond in a ring. Alkynes: Triple bonds are present; sp carbons Aromatic: Contain a benzene ring.

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Nucleophile: Donates electrons to a nucleus with an empty orbital. Electrophile: Accepts a pair of electrons. When forming a bond, the nucleophile attacks the electrophile, so the arrow goes from negative to positive. When breaking a bond, the more electronegative atom receives the electrons.

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Phủ nhúng (Dip Coating) Đế được nhúng vào dung dịch sol, sau đó được kéo ra từ từ → màng/đế Chúng tôi đã dịch được một số chương của một số khóa học thuộc chương trình học liệu mở của hai trường đại học nổi tiếng thế giới MIT và Yale.

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