NUCLEAR-CHEMISTRY-AND-RADIOACTIVE.pdf

NUCLEAR CHEMISTRY AND RADIOACTIVE Harmful Effects: Nuclear chemistry is the branch of chemistry that Acute Radiation Syndrome (ARS): Occurs deals with the study of changes in atomic nuclei. This after a high dose of rad...

NUCLEAR CHEMISTRY AND RADIOACTIVE Harmful Effects: Nuclear chemistry is the branch of chemistry that Acute Radiation Syndrome (ARS): Occurs deals with the study of changes in atomic nuclei. This after a high dose of radiation in a short period. includes radioactivity, nuclear reactions, and the Symptoms include nausea, vomiting, and, in severe cases, death. ARS was seen in effects of radiation. In this expanded view, we’ll survivors of the Chernobyl disaster (1986) cover the people involved in the discovery and and Hiroshima and Nagasaki (1945). application of nuclear chemistry, real-life examples Cancer Risk: Prolonged or high exposure to of radiation’s effects, and how nuclear chemistry is radiation increases the risk of developing applied in various fields. cancer. Marie Curie herself suffered from health complications due to prolonged Greek word Atomos, root word atom means exposure to radium and other radioactive “indivisible” materials. NUCLEAR STABILITY AND RADIOACTIVE Somatic Damage: directly harms the DEACAY organism causing sickness or death. Happens very quickly with large doses, and slowly with lower doses, often leading to cancer. Genetic Damage: Harms the reproductive RADIOACTIVITY cells, leading to problems in the offspring. Beta Particles: Can penetrate approximately Radioactivity refers to the spontaneous 1 cm. Kyrpton-85 and Strontium-90 are B- disintegration of unstable atomic nuclei, releasing producers, since Kris a noble gas, it is particles or electromagnetic radiation. The process of chemically inert, which passes through the radioactivity was discovered in 1896 by Henri body very quickly. Becquerel while investigating phosphorescent Alpha Particles: Cannot directly penetrate. materials. He found that uranium salts emitted a type Plutonium is a particularly damaging of radiation that could expose photographic plates, Gamma Ray Particles: Can directly and are even in the absence of light. highly penetrating to human tissue cause only occasional ionization. Shortly after Becquerel’s discovery, Marie and Rem: indicates the danger of the radiation Pierre Curie expanded the field by discovering two poses to humans. additional radioactive elements, polonium and radium. Their pioneering work laid the foundation Beneficial Effects: for modern nuclear chemistry. Cancer Treatment (Radiotherapy): Types of Radioactive Decay: Radiation therapy uses high-energy radiation to target and kill cancer cells. The radiation Alpha particles: The nucleus emits an alpha damages the DNA of the cancer cells, particle (two protons and two neutrons), preventing them from growing and dividing. reducing its mass number by 4 and its atomic Sterilization: Radiation is used to sterilize number by 2. Example: Uranium-238 decays medical instruments and food by killing to Thorium-234. bacteria and other pathogens without raising Beta particles: The nucleus emits a beta the temperature of the material being treated. particle (an electron or positron), converting a neutron to a proton or vice versa. Example: DETECTION OF RADIATION Carbon-14 decays to Nitrogen-14. Gamma rays: The nucleus releases excess Detecting radiation is critical for monitoring energy in the form of gamma rays. Gamma exposure in medical, industrial, and environmental rays are high-energy photons and do not contexts. Various devices are used to detect and change the composition of the nucleus. measure radiation: Photons: elementary particle that constitutes the basic unit of electromagnetic radiation, Geiger-Müller Counter: One of the most responsible for transmitting light energy. common instruments for detecting ionizing radiation (alpha, beta, and gamma radiation). EFFECTS OF RADIATION It consists of a tube filled with gas that becomes ionized when radiation passes The effects of radiation can be both beneficial and through, producing an electric signal. harmful, depending on the type, dose, and duration Scintillation Counter: Detects gamma of exposure. While radiation has many useful radiation by using materials that emit flashes applications, it can also damage living cells, of light (scintillate) when struck by radiation. potentially leading to cancer, genetic mutations, or Speed of light: 3.0 x 10^10m/s, acute radiation sickness. Equation  Occupational Safety: Workers in nuclear facilities and medical professionals who use X-rays wear personal dosimeters to ensure that they are not exposed to harmful levels of Carbon Dating: Carbon-14 dating is a radiation. The safe annual exposure limit for technique used to date ancient artifacts. It occupational workers is around 0.05 Sv. measures the amount of Carbon-14 (which undergoes beta decay) remaining in organic MEDICAL APPLICATIONS materials. Since Carbon-14 has a half-life of 5,730 years, this method is ideal for dating 1. Medicine: o Nuclear Medicine: Radioisotopes items thousands of years old. 1940’s by are used in medical imaging to Willard Libby, American Chemist. diagnose diseases. For instance, Technetium-99m is used in imaging Real-Life Application: the brain, bones, heart, and other organs. Environmental Monitoring: After nuclear o PET Scans: Positron Emission accidents like Fukushima Daiichi (2011), Tomography (PET) uses radiation detectors were used to monitor radioisotopes to produce 3D images radiation levels in surrounding areas to of metabolic processes in the body. It ensure the safety of residents and workers. helps in detecting cancer and brain Detectors are also used around nuclear power disorders. plants and in areas where radioactive o Thallium- can be used to asses the materials are handled. damage to the heart muscle in a person who has suffered a heart attack because thallium becomes concentrated in healthy muscle tissue. UNITS OF RADIATION Radiation is measured in different units, depending on what aspect is being measured (activity, absorbed 2. Energy: dose, or biological effect). o Nuclear Power Plants: Nuclear fission (splitting of atoms) is used to Becquerel (Bq): Measures radioactive generate electricity. This method decay, or the number of disintegrations per provides about 10% of the world’s second. electricity. Although efficient, it o Example: 1 Bq = 1 disintegration per raises concerns about nuclear waste second. A smoke detector contains and accidents, as seen in Fukushima about 30,000 Bq of americium-241. and Chernobyl. Gray (Gy): Measures the amount of o Fusion: combining two light nuclei to radiation absorbed by a material. 1 Gy is form heavier nucleus. equivalent to 1 joule of radiation energy o Fission: Splitting a heavy nucleus absorbed per kilogram of material. into nuclei with smaller mass o Example: A typical chest X-ray numbers delivers a dose of about 0.0001 Gy. o Chain Reaction: Each fission event Sievert (Sv): Measures the biological effect produces neutrons, the process can be of radiation on living tissue. This takes into self-sustaining. account the type of radiation and the o Critical Mass: Too small sample, too sensitivity of different tissues to radiation. many neutrons escape before they o Example: A CT scan might expose a have a chance to cause a fission event patient to about 0.02 Sv, which is and the process stop. relatively safe in a medical context but should be minimized to reduce PEOPLE INVOLVED risk. Rutherford (Rd): Non-SI unit, equal to 1. Henri Becquerel: Discovered radioactivity 1x10^6 Bq. Often used in physics in 1896 by observing that uranium salts emitted radiation that could expose 5. Conversion of Unites photographic plates. - 1 Bq = 2.7 x 10 ^ - 11 Ci 2. Marie and Pierre Curie: Pioneers in the - 1 Bq = 1 x 10 ^ 6 Rd study of radioactivity, they discovered the - 1 Ci = 3.7 x 10 ^ 10 Bq elements polonium and radium, and Marie - 1 Ci = 3.7 x 10 ^ 4 Rd Curie won two Nobel Prizes for her work in - 1 Rd = 3.7 x 10 ^ 6 Bq chemistry and physics. - 1 Rd = 3.7 x 10 ^ - 5 Ci 3. Ernest Rutherford: Discovered the nucleus of the atom and described the process of Real-Life Application: nuclear decay. Thomson’s plum model.