Dobereiner's Triads Flashcards
1
Q
Define a triad.
A
A triad is a group of three elements with similar chemical properties in which the atomic weight (relative atomic mass) of the middle element is approximately equal to the average of the other two
2
Q
What did Dobereiner observe about the elements bromine, chlorine and iodine (2)
A
That the properties of the element bromine seemed halfway between those of chlorine and iodine.
The atomic weight of bromine was halfway between chlorine and iodine. (He observed similar patterns with calcium, strontium and barium and sulfur, selenium and tellurium).
3
Q
Why was Dobereiner’s work important?
A
Because it was the earliest attempt to trace a relationship between properties of the elements and their atomic weights.
