1.The first subatomic particle to be discovered was the electron, identified in 1897 by J. J. ... After the nucleus of the atom was discovered in 1911 by Ernest Rutherford, the nucleus of ordinary hydrogen was recognized to be a single proton. In 1932 the neutron was discovered.
2.An ion is an atom that has gained or lost electrons, so it now has more or fewer electrons than it does protons. So an ion has a negative or positive charge. All atoms are isotopes and if an isotope gains or loses electrons it becomes an ion.
3.basic property of matter carried by some elementary particles that governs how the particles are affected by an electric or magnetic field. Electric charge, which can be positive or negative, occurs in discrete natural units and is neither created nor destroyed.
4.atomic number
5.A molecule is made up of atoms bonded together. So, while an atom is its own separate entity, a molecule is what you get when those atoms bond together. These might be the same elements, such as two oxygen atoms bonded together (O2), or it might be different atoms bonded together like water (H2O)
