Difference Between Radioactivity and Radiation
Radioactivity is the continuous nuclear transformation resulting in the formation of new elements. In other words, the radioactivity is the ability to release radiation. There are many radioactive elements. In a normal atom, the nucleus is firm. But an imbalance exists in the nuclei of the elements exhibiting radioactive property. This imbalance is due to the ratio of protons to neutrons. To become firm, the nuclei ends up emitting particles, process termed as a radioactive decay. Each and every radioactive element has a decaying rate, which is known as its half life. Half Life tells the time required for a radioactive element to reduce to one half of its original amount. The transformations can be ensued the emission of alpha particles, the emission of beta particles and orbital electron capture. When the number of protons is lower than the neutron, the nucleus of the radioactive element emits alpha particles. For example: Th-228 is a radioactive element that can emit alpha particles with different energies. Emission of a beta particle results in the conversion of a neutron into proton. P-32, H-3, C-14 are pure beta emitters. The radioactivity is measured by units, Becquerel or Curie.
Radiation is the process where the signs or energy particles (e.g.: Gamma rays, X-rays, photons) travel through a medium or space. The unstable nucleus of radioactive elements is trying to become firm by releasing radiation. Radiation can be either non-ionizing or ionizing. The energy is high in case of Ionizing radiation and when it hits another atom, it will be ionized, emitting another particle (e.g. an electron) or photon. The loosened photon or particle is radiation. The initial radiation will continue to ionize other material until its energy is over. The alpha emission, X-Rays, Gamma Rays, beta emission etc. are ionizing radiation. Alpha particles have positive charge and are similar to the nucleus of a He atom. They are able to travel through very short distances (that is to say a few centimeters). Beta particles are identical to electrons in the size and charge. They can travel a longer distance than alpha particles. The X-ray photons and Gamma Rays are not exactly particles. Gamma rays are made inside a nucleus and X-rays are produced in an electronic shell of an atom.
Non ionizing radiation does not emit particles of other materials, because their energy is lower. Yet they carry enough energy to excite electrons from the ground level at higher levels. They are electromagnetic radiation, so have the electric and magnetic field components parallel to each other and to the propagation direction sign. Red light, visible violet, infra red light, the microwave ovens are some examples to non ionizing radiation. We can protect ourselves from harmful radiation. The type of protection is determined by the energy of the radiation.