Applications and Effects of Nuclear Reactions

Front

Transmutation Noun

---

[trans-myoo-tey-shuhn]

Back

Transmutation

---

The conversion of an atom of one element into an atom of another element through radioactive decay processes.

---

Example: A neutron hits a large uranium nucleus, causing it to split into two smaller, different nuclei (barium and krypton), demonstrating the process of transmutation.

Front

Nuclear Fission Noun

---

[noo-klee-er fish-uhn]

Back

Nuclear Fission

---

A nuclear reaction where a heavy nucleus splits into smaller nuclei, releasing a significant amount of energy in the process.

---

Example: This diagram shows a neutron hitting a large atomic nucleus, causing it to split into smaller nuclei and release more neutrons and energy (photon).

Front

Chain Reaction Noun

---

[cheyn ree-ak-shuhn]

Back

Chain Reaction

---

A self-sustaining series of events where one nuclear reaction triggers subsequent reactions, creating a cascade of energy release.

---

Example: A neutron hits a uranium-235 nucleus, causing it to split (fission) and release more neutrons, which then hit other nuclei, continuing the reaction.

Front

Nuclear Fusion Noun

---

[noo-klee-er fyoo-zhuhn]

Back

Nuclear Fusion

---

A nuclear reaction where two or more light atomic nuclei combine to form a heavier nucleus, releasing immense energy.

---

Example: In a star, the outward pressure from nuclear fusion in the core balances the inward pull of gravity, keeping the star stable.

Front

Mass Defect Noun

---

[mas dee-fekt]

Back

Mass Defect

---

The difference between an atom's actual mass and the combined mass of its individual protons, neutrons, and electrons.

---

Example: This image uses a balance scale to show that a complete nucleus has a smaller mass than its individual protons and neutrons (nucleons) when separated.

Front

Critical Mass Noun

---

[krit-i-kuhl mas]

Back

Critical Mass

---

The minimum amount of a fissile material required to sustain a continuous, self-propagating nuclear chain reaction.

---

Example: A neutron splits a Uranium-235 atom, releasing more neutrons. Critical mass is the minimum material needed for these neutrons to sustain a chain reaction.

Front

Half-life Noun

---

[haf-lahyf]

Back

Half-life

---

The specific time it takes for half of the radioactive atoms in a given sample to undergo radioactive decay.

---

Example: This graph shows that after one half-life, 50% of a radioactive substance is left. After two half-lives, only 25% remains.

Front

Radiochemical Dating Noun

---

[rey-dee-oh-kem-i-kuhl dey-ting]

Back

Radiochemical Dating

---

A method used to determine the age of materials by measuring the remaining concentration of specific radioactive isotopes.

---

Example: While an organism is alive, it maintains a constant level of Carbon-14. After it dies, it stops taking in new Carbon-14, which then decays.

Front

Ionizing Radiation Noun

---

[ahy-uh-nahy-zing rey-dee-ey-shuhn]

Back

Ionizing Radiation

---

High-energy radiation capable of removing electrons from atoms and molecules, thereby creating ions as it passes through matter.

---

Example: This diagram shows that ionizing radiation, like X-rays and gamma rays, is on the high-energy end of the spectrum with short, frequent waves.

Front

Geiger Counter Noun

---

[gahy-ger koun-ter]

Back

Geiger Counter

---

A device that detects and measures ionizing radiation by producing an electrical pulse when radiation ionizes gas inside a tube.

---

Example: This diagram shows a radioactive source emitting particles, which enter a detector tube, causing a needle on a meter to move, indicating the presence of radiation.