Many scientists found
that triads (chemical
relationships expanded
beyond the triad). (jan 1, 1829 – jan 1, 1858)
Description:
During this time fluorine was added
to the halogen group; oxygen, sulfur,selenium and tellurium were grouped into a family while nitrogen,
phosphorus, arsenic, antimony, and bismuth were classified as another.
Added to timeline:
New timeline
Date:
