Section 10: Radioactive

SECTION 10 : RADIOACTIVE Radioactive are substances that contain unstable nuclei. In 1903, Ernest Rutherford suggested that the radiation emitted by radioactive substances could be divided into two types based on their charge. Radiation with a positive charge is called alpha rays, while those with a negative charge are called beta rays. Then a third ray was discovered which had no charge and was named gamma ray, discovered by Paul U. Vilard. Radioactive rays have the following properties: 1. 2. 3. 4. 5. Can penetrate paper or thin metal plates. Can ionize irradiated gas. Can discolor film plates. Causes ZnS-coated objects to glow (fluorescence). Can be decomposed by a magnetic field into three rays, namely α, β, γ. A. Alpha Rays (α) Alpha rays are positively charged particle radiation. This particle is the same as helium–4 nucleus ( ), has a charge of +2e– and a mass of 4 amu. This particle is a combination of 2 protons and 2 neutrons. Emission of alpha rays causes the atomic number to decrease by two, while the mass number decreases by four.Alpha rays are emitted by the nucleus at a speed of approxspeed of light. Because it has a large mass, this light has the weakest penetrating power among radioactive rays, but has the strongest ionizing power. These rays are deflected by the magnetic field towards the negative pole. B. Beta Rays (β) Beta rays are beams of electrons that originate from the atomic nucleus and have a charge senior high school. Because they are so small, these particles cannegative with massis considered massless so it is expressed with the notation . The energy of beta rays varies greatly, having greater penetrating power than alpha rays but weaker ionizing power. In a magnetic field, these rays bend towards the positive pole. Beta rays are also called high-speed electrons because they move at high speed. C. Gamma Rays (γ) Gamma rays are high-energy electromagnetic radiation, no charged and massless, which is expressed with the notation 0 . These rays are produced by excited nuclei, usually following the emission of beta or alpha rays. Gamma rays have very large penetrating power, the greatest among radioactive rays but their ionizing power is the weakest. These rays have no electrical charge so they cannot be deflected by an electric field. The uses of radioactivity include the following. A. As a Tracer 1. Medical Field Used as a tracer to detect various types of disease, including :  24Na, detects blood circulation disorders.  59Fe, measures the rate of red blood cell formation.  11C, knowing metabolism in general.  131I, detects damage to the thyroid gland.  32P, detects eye, liver and tumor diseases. 2. Industrial Sector Used to improve production quality, as in:  Food industry, gamma rays to preserve food, kill microorganisms that cause spoilage in vegetables and fruit.  Metallurgical industry, used to detect air cavities in cast iron, detect water pipe joints, cracks in aircraft, etc.  Paper industry, measuring paper thickness.  The automotive industry, studies the effect of oil and additives on the engine during engine operation. 3. Hydrology Sector  24Na and 131I, are used to determine the speed of river water flow.  Investigate underground water pipe leaks.  14C and 13C, determine the age and origin of groundwater. 4. Chemistry Used for analysis to trace chemical reaction mechanisms, such as:  With the help of the oxygen isotope-18 as a trace atom, the origin of the water molecules formed can be determined.  Neutron activation analysis.  Source of radiation and as a catalyst in a chemical reaction.  Creation of new elements. 5. Biology  Changing the nature of genes by giving radiation rays to the genes certain.  Determining the speed of compound formation in the photosynthesis process using the C-14 radioisotope.  Examining the movement of water within plant stems.  Understand ATP as an energy store in the body using the 38F radioisotope. 6. Agriculture Sector  37P and 14C, knowing the right place to fertilize.  32P, learn directions and abilities about insect pests.  Gene mutation or plant breeding.  14C and 18O, knowing metabolism and photosynthesis processes. 7. Animal Husbandry Sector  Assessing the efficiency of feed utilization for livestock production.  Reveals basic chemical and biological information as well as anti-quality in animal feed.  32P and 35S, for measuring the amount and rate of protein synthesis incolon.  14C and 3 H, for measuring the production and proportion of volatile fatty acids in the large intestine. B. As a source of radiation 1. Medical Field Used for radiation sterilization, tumor and cancer therapy. 2. Industrial Sector Used for:  Improving the quality of wood by adding irradiated monomer,wood becomes harder and more durable.  Improving the quality of textile fibers by irradiating textile fibers, so that the melting point is higher and it absorbs dyes and water more easily.  Control the thickness of the products produced, such as paper sheets, films, and metal plates.  60Co for tanning leather, so the durability of leather tanned this way is better than leather tanned the normal way. 3. Animal Husbandry Sector Used for:     Gene mutation with radiation for plant breeding. Eradicating pests by irradiating male insects so they are sterile. Preserving food with Xray or gamma radiation for kill eggs or larvae. Delays sprouting in onions, potatoes and tubers forextend storage period. The negative impacts of radioactive radiation include: 1. Radioactive radiation can shorten human life. This is because radioactive substances can cause damage to body tissue and reduce the body's immunity. 2. Radiation of radioactive substances to the sexual glands can cause infertility and genetic mutations in offspring. 3. Radiation from radioactive substances can cause white blood cells to divide, resulting in leukemia. 4. Radiation from radioactive substances can cause local somatic damage with signs of skin damage, damage to cells that form blood cells, and damage to the nervous system.