CHEMENG - Midterm Review: Radioactivity, Nuclear Processes, and Fuels (Vocabulary)

Vocabulary flashcards covering key terms from the notes on radioactivity, nuclear processes, and the chemistry of fuels.

Alpha Particle Emission

Emission of an alpha particle (a helium nucleus) from a nucleus; the parent nucleus loses 2 protons and 2 neutrons (Z − 2, A − 4).

Beta Particle Emission

Beta decay where a neutron becomes a proton, emitting an electron and an anti-neutrino; Z increases by 1, A unchanged.

Gamma Radiation

Emission of high-energy photons; Z and A stay the same; gamma rays have low ionizing power.

Positron Emission

Emission of a positron (positive electron); like beta decay but with +1 charge; Z decreases by 1, A unchanged.

K-Electron Capture

An inner-shell electron is captured by the nucleus; proton → neutron; Z decreases by 1, A unchanged; neutrino emitted.

Electron Capture

A nucleus captures an orbital electron; cascade of electrons filling levels; proton → neutron; Z decreases by 1, A unchanged; neutrino emitted.

Mass-Energy Relations

Mass defect translates into binding energy; BE = Δm c^2; connects mass, energy, and nuclear stability.

Joule

SI unit of energy; suitable for macroscopic energies, not small atomic energies.

Electron Volt (eV)

Energy gained by one electron when moved through 1 volt; 1 eV = 1.602×10^-19 J.

Mass Defect

Difference between an atom’s actual mass and the sum of the masses of its protons, neutrons, and electrons.

Binding Energy

Energy required to disassemble a nucleus into protons and neutrons; higher BE implies greater stability.

Fission

Splitting of a heavy nucleus into lighter nuclei with energy release; parent nucleus → daughter nuclei.

Fusion

Joining of light nuclei to form a heavier nucleus; product may have different neutron/proton content (e.g., H + H → He).

Fuels

Substances that burn in air to release heat for domestic or industrial use (not nuclear fuel).

Primary Fuels

Natural fuels found in nature and usable without energy-intensive processing.

Secondary Fuels

Derived fuels produced from primary fuels through processing (e.g., petrol, diesel).

Solid Fuels

Fuels in solid form (wood, charcoal, coal, peat, etc.).

Liquid Fuels

Fuels in liquid form (petrol, kerosene, diesel, alcohol).

Gaseous Fuels

Fuels in gaseous state (natural gas, producer gas, water gas, coal gas).

Wood

First known fuel used by early humans; derived from trees; historically dominant fuel.

Charcoal

Wood-derived carbon produced by slow pyrolysis (no oxygen); burns hotter with less smoke.

Coke

Grey, hard fuel made by destructive distillation of coal; used in iron smelting; pet coke from oil.

Crude Oil

Naturally occurring mixture of hydrocarbons; refined into petroleum products; separated by distillation.

Petroleum

Naturally occurring yellowish-black liquid; refined into fuels; separated by fractional distillation.

Fractional Distillation

Separation of a liquid mixture into fractions by boiling point using a fractionating column.

Fossil Fuel

Petroleum-based fuels formed from dead organisms under heat and pressure; dominant energy source since the Industrial Revolution.

Kerosene

Combustible hydrocarbon liquid derived from petroleum; used in aviation and lamps; name from keros Greek for wax.

Tar

Dark viscous liquid from destructive distillation of coal, wood, petroleum, or peat; coal tar used for paving; associated with historic oil fields such as near Baku.