Periodic Trends

metals, metalloids, non-metals

atoms, ions, compounds

protons, neutrons, electrons

lose electrons

gain electrons

are always positive numbers

are always negative numbers

are more variable

+1

+2

-1

-2

are inert

have a valence number of 8

have a full outer shell

all of the others

+1

-1

+2

-2

have a valence number of +1

are so reactive that they react explosively

are in group 1 of the periodic table

readily give away their 1 valence electron

are in group 7

have a valence of +1

can typically accept 1 electron

are inert

they have a full outer shelll

they have 8 (or 2) electrons in their outer shell

they need only 1 electron

they can donate 1 electron

they are in the middle of the periodic table

has a valence number of +4

can share 4 electrons making 4 covalent bonds

is in group 14

wants to give away its 4 electrons