Look at the model of an atom below. Does the model represent a metal atom or a nonmetal atom?
Carbon is an nonmetal, group six, it needs two electrons in its outer valence shell.
Magnesium is an Alkaline Earth Metal; group two, it has two electrons in its outer valence shell.
Calcium is an Alkaline Earth Metal, group two, it has two electrons in its outer valence shell.
Oxygen is an nonmetal, group sixteen, it needs two electrons in its outter valence shell.