Early chemists tried to look at and understand PATTERNS in ELEMENT'S PROPERTIES to get a better overall understanding
EARLY 1800s- Scientists could only go by relative atomic mass.
UNTIL QUITE RECENTLY- Only two obvious ways to categorise elements:
- Physical and chemical properties
- Relative atomic mass
At this time scientists did not know about atomic structure, protons or electrons, or atomic number. Elements were arranged in order of atomic mass.
In the 20th Century, after the discovering of electrons and protons, it was realised elements were best arranged in order of…