Chapter 11 : Reactions of substitution on aromatic cycles

Aromatic cycles, such as the benzene, are very stable because of their energy of resonance. As a result, it is very difficult to “open” the cycle by an usual reaction of addition. Instead of addition reactions, we observe reactions of substitution. The mechanism involves two steps. the first step is the electrophile attack of one […]

Chapter 10 : Reactions of carboxylic acids and their derivatives

All the atoms of carboxylic acids groups have a specific character. The group is thus ambident: it possesses two or more alternative and strongly interacting distinguishable reactive centres. It has acidic and basic properties. A carboxylic acid is more acid than the corresponding alcohol because the conjugated base, the carboxylate, is stabilised by resonance (pKa≈5 […]

Leçon 4 : les déterminants

Définition : Le déterminant est un mot qui précède un nom et qui permet à ce nom d’être utilisé dans une phrase ,il fait donc partie du groupe nominal. Il s’accorde en genre( masculin ou féminin ) et en nombre( singulier ou pluriel). Les différents types de déterminants : 1) Les articles :      a)Les Articles  définis : le, […]