Atomic and Nuclear Physics Vocabulary

Flashcards covering key vocabulary and concepts from the Atomic and Nuclear Physics lecture notes.

What are protons?

Protons are positively charged subatomic particles located in the nucleus of an atom. They determine the element's atomic number and identity.

What are neutrons?

Neutrons are electrically neutral (no charge) subatomic particles located in the nucleus of an atom. They contribute to the atom's mass but not its charge.

What are electrons?

Electrons are negatively charged subatomic particles that orbit the nucleus in specific energy levels or shells. Their arrangement determines the chemical properties of an atom.

What is the strong nuclear force?

The strong nuclear force is a fundamental force that holds protons and neutrons together within the nucleus, overcoming the electrostatic repulsion between protons. It is one of the four fundamental forces of nature.

What is the atomic number (Z)?

The atomic number (Z) is the number of protons in the nucleus of an atom, which uniquely identifies the element. For example, all atoms with an atomic number of 1 are hydrogen atoms.

What is the mass number (A)?

The mass number (A) is the total number of protons and neutrons in the nucleus of an atom, representing its approximate mass. It is used to distinguish between different isotopes of an element.

What are isotopes?

Isotopes are atoms of the same element (same number of protons) that have different numbers of neutrons, resulting in different mass numbers. For example, carbon-12 and carbon-14 are isotopes of carbon.

What is radioactivity?

Radioactivity is the spontaneous decay of an unstable nucleus, resulting in the emission of nuclear radiation such as alpha particles, beta particles, or gamma rays. This process transforms the nucleus into a more stable configuration.

What are alpha particles?

Alpha particles are particles consisting of two protons and two neutrons, equivalent to a helium nucleus (\alpha), emitted during radioactive decay. They have a positive charge and relatively low penetration power.

What does it mean to balance nuclear equations?

Balancing nuclear equations means ensuring that the total number of nucleons (protons and neutrons) and the total charge are conserved on both sides of a nuclear reaction equation. This ensures mass and charge are balanced in the nuclear process.

What are beta particles?

Beta particles are high-speed electrons or positrons emitted from the nucleus during radioactive decay (\beta). They have a higher penetration power than alpha particles but are less ionizing.

What is beta decay?

Beta decay is a type of radioactive decay in which a neutron in the nucleus transforms into a proton and an electron (beta particle), or a proton transforms into a neutron and a positron. This process changes the atomic number of the nucleus.

What are gamma rays?

Gamma rays are high-energy electromagnetic radiation emitted from the nucleus during radioactive decay (\gamma). They have the highest penetration power and are highly ionizing.

What is ionization?

Ionization is the process by which radiation removes electrons from atoms, creating ions. This can disrupt chemical bonds and cause biological damage.

What is half-life?

Half-life is the time required for half of the radioactive nuclei in a sample to decay. It is a characteristic property of each radioactive isotope and is used in radiometric dating.

What is radio carbon dating?

Radio carbon dating is a method for determining the age of organic materials by measuring the amount of carbon-14 (^{14}C) remaining in a sample, which is formed when nitrogen is hit by neutrons. It is useful for dating materials up to about 50,000 years old.

How do smoke detectors work?

Smoke detectors use alpha particles to ionize air and create a current; smoke particles interfere with this current, triggering an alarm. This type of detector is effective at detecting rapidly burning fires.

How are gamma rays used in medicine?

Gamma rays are used in medicine to kill cancer cells (radiation therapy) or for medical imaging (e.g., gamma cameras). The high energy of gamma rays allows them to penetrate tissues and target specific areas.

What are radioactive tracers?

Radioactive tracers are radioactive isotopes used to trace the path of substances in biological or environmental systems (e.g., monitoring chemical uptake by plants). Their radioactivity allows for easy detection and tracking.

What is irradiation, and what is it used for?

Irradiation is the process of exposing materials to radiation for sterilization or other purposes. It is used to kill bacteria and viruses in food, medical equipment, and other products.

What are nuclear reactions?

Nuclear reactions are reactions involving the nuclei of atoms, which can result in the formation of new nuclei. These reactions involve changes in the number of protons and/or neutrons in the nucleus.

What is nuclear fission?

Nuclear fission is a nuclear reaction in which a heavy nucleus splits into two or more smaller nuclei, releasing a large amount of energy. This process is used in nuclear power plants and atomic bombs.

What is nuclear fusion?

Nuclear fusion is a nuclear reaction in which two light nuclei combine to form a heavier nucleus, releasing a large amount of energy. This process powers the sun and other stars.

How does a nuclear power station work?

A nuclear power station uses nuclear fission of uranium-235 (^{235}U) to generate heat, which is used to produce steam that drives turbines and generates electricity. The process involves controlled nuclear reactions to produce a sustainable energy source.