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Substitution:◦ Polar

◦ Non-polar

H

BrHH + KCN

H

NCHH + KBr

CH4 + Cl2 CH3Cl + HCllight (h)

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Mechanism: Complete step-by-step of exactly which bonds break and which bonds form and in what order.

Thermodynamics: The study of the energy changes that occur in chemical transformations. This allows for comparison of stability of reactants and products.

Kinetics: The study of reaction rates, determining which products are formed most rapidly. One can predict how the rate will change with changing conditions.

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rate = kr[A] [B]a b

CH3Br + OH CH3OH + Br

Rate = k[CH3Br][OH ]

second order rate kinetics

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(CH3)3CBr + H2O (CH3)3OH + HBr

Rate = k[(CH3)3CBr]

First order rate kinetics

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Chlorination does not occur at room temperature in the dark.

The most effective wavelength of light is blue that is strongly absorbed by Cl2 gas.

The light-initiated reaction has a high quantum yield (many molecules of product are formed from each photon of light).

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It is the change that occurs in a system when one mole of matter is transformed by a chemical reaction under standard conditions

Bond Dissociation Energy the amount of energy which is required to homolytically fracture a chemical bond

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60%

40%

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C

CH3

CH3

CH3 H HCH3

CH3

CH2

C CH3

CH3

CH3

C.++ Cl

.

.

.

C

CH2

CH3

CH3 H

.C

CH3

CH3

CH3

+ Cl2

+ Cl2 C

CH3

CH3

CH3 Cl

C

CH2Cl

CH3

CH3 H 65%

35%

+ Cl

+ Cl

.

.

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.O3 O2 + Oh

C Cl

F

F

Cl Cl

F

F

C . .

. .

. .

Cl+

Cl + O3 ClO + O2

ClO + O Cl . + O2

O3 + O 2 O2.net reaction

i)

ii)

hultraviolet

a CFC

04/20/23 24Dr Seemal Jelani

ThemeOne Nucleophile is substituted for another nucleophile

General reaction

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A species that loves a nucleusSince nuclei are positively charged, so nucleophiles are negatively charged or bear a partial negative charge

Examples are lone pairs or a hydroxide ion.

Nucleophile is an electron rich species.

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An ion or molecule that is electron deficient and can accept electrons

Electrophiles are often reducing agents and Lewis acids

They are either positive ions (e.g. NO2 +) or

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molecules that have a positive charge on a particular atom(e.g. SO3, which has an electron-deficient sulphur atom)

In organic reactions they tend to attack negatively charged parts of a molecule

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Nucleophiles can be classified according to the kind of atom that forms a new covalent bond.1. Oxygen Nucleophile

(HO-, CH3O)

2. Nitrogen Nucleophiles (NH3,

RNH2…)

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3 Sulfur Nucleophiles (HS-, RS- …)

4 Halogen Nucleophiles (I-..)

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