Atoms are particles of elements, substances that could not break down further. In examining atomic structure through, we have to clarify this statement. An atom cannot be broken down more without altering the chemical nature of the substance. For example, if you have 100 watches, they all behave like watches and tell time. You can destroy one of the watches: take the back off, remove the batteries, peer inside and drag things out. However, now the watch no longer acts like a watch. So what does as atom look like inside? Atoms are constituted of 3 types of particles protons, electrons and neutrons. These particles have different types of properties. Electrons are small, very light particles that possess negative charge (-). Protons are larger and heavier than electrons and own the opposite charge. Each atom is made up of a grouping of these particles. The charge of an electron is exactly equal and opposite to that of a photon. This elementary charge e is 1.6*1-19C. The mass of a proton or a neutron is 1.673*10-19C. The mass of an electron is only 0.911*10-27 all the protons and the neutrons which constitute an atom combine to form its nucleus. Thus, the nucleus consists of all the positive charge and almost the whole mass of the atom. The nucleus is a very dense positively charged mass. The negatively charged electrons of the atom move round the positively charged nucleus. The number of electrons there in an atom is equivalent to the number of protons. Consequently, an atom is a neutral particle. The proton an electron stays together because just like two magnets, the opposite electrical charges attract each other. What keeps the two from crashing into each other? The particles in an atom are not at rest. The electron is continuously spinning around the nucleus. The centrifugal force of the spinning electron puts the two particles from coming into contact with each other much as the earth's rotation keeps it from plunging into the sun. Every atom of an element consists of the same number of protons. The atomic number of an element indicates the number of protons present in each one of its atoms. The periodic table of elements displays elements arranged with increasing atomic number. It contains the symbols and number of the elements. The number of neutrons present in the atom of an element can vary. Thus, each atom of an element consists of the same number of protons, but may have dissimilar number of neutrons. Such atoms are called isotopes. Many elements can exist in a number of isotopic forms. The atomic weight or weight of each atom is given relative to the atomic mass of the carbon isotopes C12.