Ch25 Nuclear Chemistry Review

Describe alpha particles

Heavy, positively charged particles containing two protons and two neutrons, is identical to the nucleus of a helium atom; can be emitted during radioactive decay

What is radiation?

rays and/or particles that are emitted spontaneously by radioactive materials

Describe gamma radiation

High-energy radiation that has no mass and travel as light waves (very damaging radiation) emitted by radioactive materials.

Describe beta radiation

like a fast moving electron emitted from the nucleus; produced when a neutron decays into a proton

What initiates fission and what happens?

Collision with a neutron causes an atom to split into two smaller nuclei - exothermic

Produces multiple neutrons which starts chain reaction

Used in nuclear power plants to create energy and in atomic bombs

Describe basics of fusion reactions

Small, fast-moving elements collide and create new, more stable elements

Releases the most energy

Used in the sun/stars and nuclear bombs but not in power plants

What is half-life

time it takes for 1/2 of element to decay into another isotope

symbol of alpha particle

⁴₂He

symbol of beta particle

⁰₋₁e

symbol of gamma particle

⁰₀γ

Fraction of original sample left after 3 half lives

1/8 of original sample (1/2 x 1/2 x 1/2)

Highest atomic # element that can be found in nature

Uranium

Highest atomic # element that has at least one stable isotope

Pb or Bi (Bismuth has an isotope that has extremely long half life, almost considered stable)

symbol for neutron

¹₀n