Unit 3 test Flashcards
Who was the first to introduce the idea of the atom?
Demecrotis
Who re introduced the atom
Dalton
The early modern periodic table credited to
Mendeleeve
In the early modern periodic table it was arranged how?
increasing atomic mass (periods) and characteristics (groups)
What is the important result of the early periodic table?
The existence and properties of an undiscovered property could be predicted.
what group is chlorine in?
halogen
what group is iron in?
Transition metals
what group is sodium in?
Alkali metals
what group is helium in
noble gases
what group is uranium in?
inner transition
what is the atomic mass?
the number at the bottom of the element and the number of protons plus the number of neutrons. Also how much it weighs.
what is the atomic number?
The atomic number is the top number on the element and is the number of protons.
What are the colums called
groups
what is a row called
period
which elements luster and conduct heat
metals