- - handle;
- - paper;
- - periodic system of elements.
for the correct spelling of the structural formula of a chemical substance, you should be familiar with and to represent what is the ability of atoms to form a certain number of pairs of electrons with other atoms.After all, it will help you to draw the valence chemical bonds.For example, given a molecular formula of ammonia NH3.You must write the structural formula.Consider the fact that hydrogen is always univalent, so its atoms can not be linked together, so they will be connected to the nitrogen.
To properly write the structural formulas of organic compounds, repeat the basic tenets of the theory AMButlerova whereby isomers exist - a substance with the same basi
c structure, but with different chemical properties.For example, isobutane and butane.Molecular formula they have the same: C4H10, and structural - are different.
In the linear formula, each atom is recorded separately, so that image takes a lot of space.However, for the structural formulas, you can specify the total number of hydrogen atoms for each carbon atom.A draw between adjacent carbons chemical bonds in the form of lines.
Writing isomers start with the normal structure of hydrocarbon that is a straight chain of carbon atoms.Then cut one carbon atom that is attached to another internal carbon.Having exhausted all spellings isomers of the chain length, cut it one more carbon atoms.Again, attach it to an internal carbon atom chain.For example, the structural formula of n-pentane, isopentane, tetrametilmetana.Thus, a hydrocarbon with molecular formula C5H12 has three isomers.
to determine the valence of the atoms in the preparation of the structural formulas use the periodic system.Show exact distance of the atoms in the molecule helps the three-dimensional structural formula.
- structural formula of substances