Define radioactivity and radioactive decay. Describe common types of radioactive decay and provide examples.

Welcome back Ratibuh — missed you this week. Item 1: i) Step 1: Define radioactivity. Radioactivity is the spontaneous emission of radiation from the unstable nuclei of certain atoms. This process occurs when an atomic nucleus has excess energy and attempts to reach a more stable state. Step 2: Define radioactive decay. Radioactive decay is the process by which an unstable atomic nucleus loses energy by emitting radiation, such as alpha particles, beta particles, or gamma rays, transforming into a different, more stable nucleus. ii) Here are common types of radiative decays: • Alpha Decay: An unstable nucleus emits an alpha particle (^4_2He), which consists of two protons and two neutrons. This reduces the atomic number by 2 and the mass number by 4. ^A_ZX ^A-4_Z-2Y + ^4_2He For example, Uranium-238 decaying into Thorium-234: ^238_92U ^234_90Th + ^4_2He • Beta Decay (Beta-minus Decay): A neutron in the nucleus transforms into a proton, emitting an electron (beta particle, ^0_-1e) and an antineutrino. This increases the atomic number by 1, while the mass number remains unchanged. ^A_ZX ^A_Z+1Y + ^0_-1e + _e For example, Carbon-14 decaying into Nitrogen-14: ^14_6C ^14_7N + ^0_-1e + _e • Gamma Decay: This occurs when a nucleus in an excited state releases energy in the form of a gamma ray ( photon) to transition to a lower energy state. There is no change in the atomic number or mass number of the nucleus. ^A_ZX^* ^A_ZX + (where ^* denotes an excited state) iii) Step 1: Explain the dangers of radiation. The dangers of radiation include cellular damage, which can lead to cancer, genetic mutations in reproductive cells, and acute radiation sickness at high doses. Radiation can disrupt biological processes by ionizing atoms and molecules within the body. Step 2: Advise on safety precautions. • Time: Minimize the duration of exposure to the radiation source. • Distance: Maximize the distance from the radiation source, as radiation intensity decreases significantly with distance. • Shielding: Use appropriate shielding materials (e.g., lead, concrete, thick earth) between yourself and the source to absorb radiation. • Contamination Control: Avoid ingesting or inhaling contaminated materials, such as washing vegetables thoroughly or avoiding consumption if contamination is severe. Item 2: a) Step 1: Address the World Cup time zone misunderstanding. The difference in time between Brazil and East Africa during the World Cup is due to Earth's rotation on its axis. As the Earth spins, different parts of the globe are exposed to the sun, creating day and night. Time zones are established based on longitude, meaning that when it is night in East Africa, it can be daytime in Brazil because they are located at different longitudes. Step 2: Address the planetary habitability misunderstanding. NASA's statement that Earth is the only planet known to support life refers to the unique combination of conditions present on Earth. These include the presence of liquid water, a suitable atmospheric composition (rich in oxygen and nitrogen), a stable temperature range, and a protective magnetic field. While other celestial bodies might have some of these factors, none are currently known to possess all the necessary conditions to sustain complex life as we understand it. This highlights the specific physical requirements for life and the rarity of such conditions in the universe. b) The task for part b) is not visible in the provided image. Please send the full question for part b) so I can help you with it! 📸