Physics
In this educational lesson, nuclear reactions are discussed, focusing on isotopic notation, nuclear fusion, nuclear fission and various types of radioactive decay. An element written in isotopic notation includes its mass number (A) as a superscript and atomic number (Z) as a subscript. Nuclear fusion involves combining nuclei to form heavier nuclei, while nuclear fission describes splitting nuclei into lighter nuclei.
Radioactive decay includes alpha decay (emission of an alpha particle, which is similar to a helium nucleus), beta minus decay (a neutron decaying into a proton, emitting an electron), beta plus decay (decay of a proton into a neutron, emitting a positron), electron capture (a proton absorbing an electron to become a neutron), and gamma decay (emission of high energy photons from an isotope's nucleus). These decays affect the mass number and atomic number of isotopes in different ways, ultimately altering their compositions.
Lesson Outline
<ul> <li>Isotopic Notation <ul> <li>Mass number (A) represents the total number of protons and neutrons in an atom's nucleus</li> <li>Atomic number (Z) represents the total number of protons in an atom's nucleus</li> </ul> </li> <li>Nuclear Fusion <ul> <li>Combining multiple light nuclei to make a heavier nucleus</li> </ul> </li> <li>Nuclear Fission <ul> <li>Splitting an atom's nucleus into two or more lighter nuclei</li> </ul> </li> <li>Radioactive Decay <ul> <li>Alpha Decay <ul> <li>Emission of alpha particles, equivalent to a Helium nucleus</li> <li>Decreases an isotope's mass number by 4 and atomic number by 2</li> <li>Alpha particles struggle to penetrate most surfaces</li> </ul> </li> <li>Beta Minus Decay <ul> <li>Occurs in unstable nuclei with too many neutrons compared to protons</li> <li>Neutron decays into a proton, emitting an electron in the process</li> <li>Isotope's atomic number increases by 1; mass number stays the same</li> </ul> </li> <li>Beta Plus Decay <ul> <li>Occurs in unstable nuclei with too many protons compared to neutrons</li> <li>Proton decays into a neutron, emitting a positron in the process</li> <li>Isotope's atomic number decreases by 1; mass number stays the same</li> </ul> </li> <li>Electron Capture <ul> <li>Occurs when a proton absorbs an electron to become a neutron</li> <li>Isotope's atomic number decreases by 1; mass number stays the same</li> </ul> </li> <li>Gamma Decay <ul> <li>Occurs when a nucleus emits high-energy photons (light particles)</li> <li>Does not change atomic number or mass number of isotope</li> </ul> </li> </ul> </li> </ul>
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FAQs
Nuclear fission is the process by which an atomic nucleus splits into two smaller nuclei, releasing energy in the process. This is commonly seen in radioactive decay and is employed in nuclear power plants. Nuclear fusion, on the other hand, is the process by which two atomic nuclei combine to form a larger nucleus, releasing large amounts of energy. This reaction occurs in the core of stars, including our sun, where hydrogen atoms fuse to form helium.
Isotopic notation is a way to represent the different isotopes of an element, showing its mass number and atomic number. The mass number (A) is the sum of the number of protons and neutrons in the nucleus, while the atomic number (Z) is the number of protons. Isotopic notation is typically written as AZX, where X represents the chemical symbol of the element. For example, carbon-14 is written as ¹⁴₆C, with 14 being the mass number and 6 being the atomic number.
There are several types of radioactive decay processes that can occur during nuclear reactions, including alpha decay, beta minus decay, beta plus decay, electron capture, and gamma decay. Alpha decay involves the emission of an alpha particle, which consists of 2 protons and 2 neutrons. Beta minus decay occurs when a neutron is converted into a proton and an electron, which is emitted as a beta particle. Beta plus decay is the opposite, where a proton is converted into a neutron and a positron, with the positron emitted. Electron capture is when a proton-rich nucleus absorbs an electron, turning a proton into a neutron. Gamma decay is the emission of a high-energy photon, called a gamma ray, as the nucleus transitions from an excited state to a lower energy level.
