the atom
the atom is made up of protons neutrons and electrons
the atom is made up of three subatomic particles -protons,neutrons and electrons Protons are heavy and positively charged neutrons are heavy and neutral electrons have hardly any mass and are negatively charged
the nucleus
1) the nucleus is in the middle of the atom
2) it contains protons and neutrons
3) it has a positive charge because of the protons
4) almost the hole mass of the atom is concentrated in the nucleus
Molecules are made-up from 2 or more atoms held together by covalent bonds
molecules can be made of the same element or different element simple molecules are pretty tiny (like atoms)
the bonds that from between these molecules are generally a similar length to the atomic diameter