A chemist in an imaginary universe, where electrons have different charge than they do in our universe, performs the Millikan oil drop experiment to measure the electrons charge. The charge of several drops are recorded below

If a hydrogen atom is neutral, it must also have  one electron. an oxygen atom (o) has an atomic number of eight (8). this means a neutral oxygen atom has eight protons and eight electrons. the element actium (ac) has an atomic number of 89, so it has 89 protons and 89 electrons in a neutral atom

Matter- occupies space and possesses rest massno matter is the opposite