There are several isomers of benzene congeners containing 8 carbon atoms!!

A homolog of benzene containing 8 carbon atoms, that is, there are 2 carbon atoms in addition to the benzene ring, and the 2 carbon atoms can form 1 ethyl group or 2 methyl groups. Therefore, its isomers are ethylbenzene with one ethyl group attached to the benzene ring, and three xylene with two methyl groups linked to the benzene ring. (o-xylene, m-xylene, paraxylene).

There are 22 isomers of benzene homolog C10H14 from the molecular formula, and there is a benzene ring and an alkyl group in its structural formula. 1. There is only one alkyl group: that is, butanekyl group, and there can be 4 kinds of butyl group, so there can be 4 isomers; 2. There are two alkyl groups:

It is divided into one methyl group, one propyl group (there are two forms of propyl group) There are 6 kinds of critical pairs of benzene rings in total When both are ethyl groups There are 3 kinds of critical pairs There are 9 kinds of this kind of case in total 3. There are three alkyl groups 2 methyl groups 1 ethyl group First of all, 2 methyl groups There are three cases of critical pairs When the methyl groups are adjacent to each other, there are 3 kinds When the methyl groups are interphased, there are 1 kinds There are 6 kinds in total! 4. When there are four methyl groups, there are 1 kind of 4 methyl groups adjacent to each other, 1 kind of three class A adjacent ones, 1 kind when two methyl groups are connected, there are 3 kinds in total, and the sum of the four cases is 22 kinds.

What is the chemical formula of the substance you are asking? 8 carbons are too broad, for example, a substituent can be ethyl, vinyl, benzyl, etc., 2 substituents are 2 methyl groups, there will be position isomerism, and different para-positions between neighbors are different isomers, summarize it yourself.

Pro-C9H12 benzene homologues refer to molecules formed by one or more hydrogen atoms on the benzene ring being replaced by other groups. Since the benzene ring itself is a planar molecule, the coplanar properties of all substituents in benzene and its congeners are similar to those of benzene rings, depending on factors such as the size, shape, and position of the groups in the benzene ring. We can try to list some possible C9H12 benzene homologues, such as 1,2,3-trimethylbenzene, 1,2,4-triethylbenzene, 1,2,3,5-tetrapropylbenzene, etc.

For these molecules, there are only a maximum of six carbon atoms coplanar, because only a maximum of six groups can be attached to the benzene ring at the same time, and these groups are often placed far away from the plane of the benzene ring, so it is difficult to keep the entire molecule in the same plane.

Three substituted, three kinds. Even trimethylbenzene is known to sell, partial trimethylbenzene, all trimethylbenzene, and teasing.

Two replaced, 3 kinds. o-methylethylbenzene, m-methylethylbenzene, p-methylethylbenzene, one substituted, 2 kinds. N-cumene, cumene.

A total of 8 types of '<>

According to the degree of unsaturation. One benzene ring and two carbon-carbon triple bonds have the same degree of unsaturation. Therefore, there are 10 types of structures, and only the carbon skeleton is analyzed.

There are 22 kinds of this in total.

1. There is only one alkyl group: that is, butanekyl group, and there can be 4 kinds of butyl group, so there can be 4 isomers;

2. There are two alkyl groups:

It is divided into one methyl group, one propyl group (there are two forms of propyl group) There are 6 kinds of critical pairs of benzene rings in total When both are ethyl groups There are 3 kinds of critical pairs There are 9 kinds of this kind of case in total 3. There are three alkyl groups 2 methyl groups 1 ethyl group First of all, 2 methyl groups There are three cases of critical pairs When the methyl groups are adjacent to each other, there are 3 kinds When the methyl groups are interphased, there are 1 kinds There are 6 kinds in total!

4. When there are four methyl groups, there are 1 species of 4 methyl groups adjacent to each other, 1 species of three class A adjacent groups, 1 species when two methyl groups are connected, and there are 3 species in total.

The sum of the four conditions is 22.

The first substance, the axis of symmetry (plane) is drawn, there are a total of 6 hydrogen on the two methyl groups, and they are symmetrical, so they are equivalent hydrogen. Then the hydrogen at positions 1 and 4 on the benzene ring is equivalent hydrogen, and 2 and 3 are equivalent hydrogen.

The latter three species do not have an axis of symmetry (face), so there is no equivalent hydrogen except that hydrogen attached to the same carbon atom is equivalent hydrogen (e.g., three hydrogen on -ch3 are equivalent hydrogen).

The carbon atoms on the benzene ring backbone are not arranged by single and double bonds as previously known (proposed by Kekuler), but the bonds between each two carbon atoms are the same, and are connected by a bond that is neither double nor single (large bond).

<> hope it helps you and hopefully

There are 20 in total instead of 19.

There is one less case where there is only one side chain on the benzene ring: an amino group on the carbon attached to the benzene ring.