What are the types of reactions in high school chemistry?

Substitution reaction refers to the reaction in which some atoms or atomic groups in organic molecules are replaced by other atoms or atomic groups. Including halogenation, nitration, sulfonation, hydrolysis of halogenated hydrocarbons, esterification, hydrolysis of esters, etc. Due to the widespread existence of substitution reaction, almost all organic substances can undergo substitution reaction.

2. Addition reaction

Addition reaction refers to the reaction that unsaturated carbon atoms in organic molecules directly combine with other atoms or groups to form new compounds. Including addition reaction with hydrogen (catalytic hydrogenation of olefins, alkynes and benzene rings; Catalytic hydrogenation of aldehydes and ketones; Hydrohardening of oils and fats), addition reaction with halogen, addition reaction with hydrogen halide, addition reaction with water, etc. Only unsaturated organic compounds can undergo addition reaction.

Step 3 eliminate the reaction

Elimination reaction refers to the reaction of removing small molecules (such as water, HX, etc.) by organic matter. Under appropriate conditions, unsaturated (double bond or triple bond) compounds are generated from one molecule. Includes elimination reaction of alcohol and elimination reaction of halogenated hydrocarbon. In middle school, phenol cannot be eliminated, and not all alcohols or halogenated hydrocarbons can be eliminated.

4. Dehydration reaction

Dehydration reaction refers to the reaction of removing hydrogen and oxygen equivalent to water from organic matter under appropriate conditions. Include intramolecular dehydration (elimination reaction) and intermolecular dehydration (substitution reaction). Dehydration reaction is not necessarily an elimination reaction, for example, dehydration of ethanol into ether is not an elimination reaction.

5. Hydrolysis reaction

Hydrolysis in a broad sense refers to any reaction with water. In middle school organic chemistry, substances that can hydrolyze with water generally refer to the hydrolysis of halogenated hydrocarbons, esters, oils (including saponification), sugars, peptides or protein.

6. Oxidation reaction

Oxidation reaction refers to the reaction of adding oxygen or removing hydrogen to organic matter. Including:

① Catalytic oxidation of alcohol: the O-H bond of hydroxyl group is broken, the C-H bond of carbon atom connected with hydroxyl group is broken, and hydrogen atom is removed to form C = O bond;

(2) the reaction of aldehydes and compounds containing aldehyde groups with newly prepared alkaline copper hydroxide or silver ammonia solution;

(3) ethylene is oxidized to methanol; In the presence of a catalyst;

④ The burning of organic matter, unsaturated hydrocarbon homologues and benzene makes the acidic KMnO4 solution fade.

⑤ Phenol is put in the air and converted into pink substance (quinone).

7. Reduction reaction

Reduction reaction refers to the reaction of hydrogenation or deoxidation of organic matter. Include catalytic hydrogenation of aldehydes, ketones, olefins, alkynes, benzene and its homologues, phenols, unsaturated oils and other organic substances.

8. Esterification reaction

Esterification refers to the reaction between acid and alcohol to produce ester and water. Esterification reaction belongs to substitution reaction, but not all reactions that produce esters belong to esterification reaction, such as the reaction of Ch3coona+Ch3ch2br → Ch3cooch2CH3+Nabr.

9. Polymerization

Polymerization refers to the reaction of small molecular monomers with each other to produce high molecular compounds. Including addition polymerization (addition polymerization of olefins, alkynes and dienes) and polycondensation (polycondensation of hydroxy acids and amino acids, polycondensation of dicarboxylic acids and diols, and aldol condensation of phenol and formaldehyde).

10, cracking reaction

Cracking reaction refers to the reaction of cracking long-chain hydrocarbons with high relative molecular weight and boiling point into short-chain hydrocarbons with low relative molecular weight and boiling point under certain conditions. Deep cracking is called cracking.

1 1, nitration reaction

Nitrification is the reaction of introducing nitro (-NO2) into the molecules of organic compounds. Nitrification is a substitution reaction. Nitrification in middle school chemistry includes the nitration of benzene and toluene.

12, color reaction

Color reaction refers to the chemical reaction that converts the components in the sample into colored compounds. Color reactions include:

① After dropping ferric chloride solution, the phenol solution turns purple.

② Starch solution turns blue after adding iodine water.

③ protein (with benzene ring in its molecule) turns yellow after adding concentrated nitric acid (yellow protein reaction).