Some substances may have the same molecular formula and have different properties and names.

Here are two examples of chemicals that have the same molecular formula but differ in name and some properties:

Molecular Formula: C2H6O
Name: ethanol
Function: Alcohol
Melting point: -115 ° C
Boiling Point: 78 ° C
Reactivity: High
Physical state at 25 ° C: liquid

Molecular Formula: C2H6O
Name: methoxy methane
Function: ether
Melting point: -140 ° C
Melting point: -24 ° C
Reactivity: Low
Physical state at 25 ° C: gas

See the other analogous example:

What words could you write with the letters RMAO with different arrangements? We could write the words love and rome.

The same goes for substances. For this phenomenon, which is so common, we call it isomerism.

Isomeria It is the phenomenon that occurs between molecules with the same molecular formula but which differ in their structure, property and name.

The compounds that suffer from this kind of phenomenon are called isomers. The word isomer derives from two Greek radicals: iso, which means equal, and mere, which means parts.

Isomerism can be divided into:

- flat isomerism (chain, position, metameria, function and tautomeria)
- spatial isomerism (geometric cis-trans and optical)