1
I order the elements according to their atomic mass
2
I participate to propose more structured periodic tables
3
I group some elements in threes (triads) according to their atomic masses
4
identified 27 chemical elements, the element concept as a simple substance and classified the elements into metals, non-metals, transition metals and metalloids,
5
Theory states that atoms tend to stability by having eight electrons in their valence shell
6
showed the results of its atomic mass determination and established the relations between masses
7
I observe the repetition of the properties of the elements in periods of seven, such as the musical notes
8
was based on the physical properties of the elements (atomic volume, melting points and boiling
9
establishes the existence of five families (hydrogen, carbon, nitrogen, fluorine and oxygen)
10
scientist who developed a way to graphically represent the valence electrons
