1. Chemical formulas are established after repeated and serious chemical analysis of chemical compounds.
2. And, if you want, searching the formula in a catalog - if you know the name of this compound or the CAS number.
The chemical formula is representative for a molecule and give indication about the chemical composition.
One method is through spectroscopy, where molecules interact with light in different ways based on their chemical structure. By analyzing how a molecule interacts with light, scientists can determine its composition and structure. Techniques like infrared spectroscopy, mass spectrometry, and nuclear magnetic resonance (NMR) spectroscopy are commonly used for this purpose.
The term solution can be used to identify a mixture that has the same composition throughout.
..........Is necessary to know the composition of the compound.
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