more periodic table Flashcards
Atomic Mass
Mass of set numbers of atoms in an element. Mass made up of protons, electrons, neutrons. Number located top left corner. Set Number = mole. Mole = 6.02 X 1023
atomic number
Number of protons in an atom of an element. Identifies the element.
Whole number; bottom left.
Ex: H 1 proton, Au 79 protons.
Valence electrons
Number of electrons in the outer most shell
where are the electrons?
on the shells
family
Column on the Periodic Table (up and down) Same number of valence electrons. Similar chemical properties
Reacts in a similar way
period
Row on the Periodic Table (side to side)
Same number of shells. Maximum of 7 shells
Noble gas family
Family that has He on top. Full outer shell. Does not naturally form compounds
Halogen Family
Family that has F on top 7 valence electrons
Very reactive because it needs to get rid of only one electron to have a full shell
Always in a compound
Ex Cl2, NaCl
Alkani Fam
Li family
1 VE
Very reactive metal because it need to getrid of 1 electron
Always in a compound
Alkaline Metal Family
Mg family
2 VE
Fairly reactive family because it needs to get rid of 2 electrons
John Dalton
Theory that all things made up of atoms and atoms form compounds
1804
Ernest Rutherford
Discovered nucleus and nucleus is positive
1911
Neils Bohr
Theory that electrons move around in orbit
1913
James Chadwick
Discovered the neutron
1932
Dmtri Mendeleev
Organized Periodic Table
