Chemical formula that compound will be made up of the same elements in the same proportion or ratio. For example, any water molecule is always made up of two hydrogen atoms and one oxygen atom in a 2:1 ratio. If we look at the relative masses of oxygen and hydrogen in a water molecule, we see that 94% of the mass of a water molecule is accounted for by oxygen and the remaining 6% is the mass of hydrogen. This mass proportion will be the same for any water molecule. The alkene called but-2-ene has two isomers, which the chemical formula CHCH=CHCH
Rydberg formula the historical importance of this law, which was derived empirically at about the same time it was explained by the Bohr model of the atom. For other spectral transitions in multi-electron atoms, the Rydberg formula generally provides "incorrect" results, since the magnitude of the screening of inner electrons for outer-electron transitions is variable and not possible to compensate for in the simple manner above. Rydberg formula The Rydberg formula is used in atomic physics to describe the wavelengths of spectral lines of many chemical elements. It was formulated by the Swedish physicist Johannes Rydberg, and presented on 5 November 1888.