Radioactivity

Flashcards about radioactivity and nuclear physics, covering concepts like radioactive decay, types of radiation, half-life, and practical/clinical applications.

What is the electric charge of an electron?

1.6 x 10^-19 coulombs (C)

What particles are nucleons composed of?

Protons and Neutrons

What is the electric charge of an up quark?

2/3 electric charge

What is the electric charge of a down quark?

-1/3 electric charge

What is the quark composition of a proton and its resulting charge?

UQ + UQ + DQ = +1

What is the quark composition of a neutron and its resulting charge?

DQ + DQ + UQ = 0

What are isotopes?

Atoms with the same atomic number but different mass numbers; can be stable or unstable.

What is radioactive decay?

An unstable atom loses energy through the emission of particles (radiation).

What are the three main types of radiation emitted during radioactive decay?

Alpha (α), Beta (β), or Gamma (γ)

What is the unit of measurement for radioactivity?

Becquerel (Bq)

What is the Strong Nuclear Force (SNF)?

Holds the nucleus together by exchanging kinetic energy between nucleons in close contact.

What is the Weak Nuclear Force (WNF)?

Responsible for radioactive decay; as mass increases, SNF cannot hold nucleons together.

What are radiopharmaceutical tracers?

A radioisotope attached to a compound that enters the body and emits radiation, which is converted into a digital image.

What is half-life (t1/2)?

Time taken for the activity of a radioisotope to reduce by half of its initial rate.

What happens to Technetium-99m during gamma decay?

Technetium-99m undergoes gamma decay and becomes Technetium-99.

What happens during gamma decay?

High energy gamma ray is released. No particle emission. Unstable atom with excess energy aiming for stable state

What materials can Beta radiation penetrate?

Paper, plastic, tissue

What materials can Gamma Radiation penetrate?

Steel, lead

What is alpha decay and why is it so dangerous?

Most dangerous type of radiation, a helium neucleus (He+)

What happens to a large nucleus during alpha decay?

Emits energy and an α particle to achieve stability, losing 4 from the mass number and 2 from the atomic number.

What materials can Alpha radiation penetrate?

Cannot penetrate paper (0.09mm) or epidermal tissue, but can cause erythema (burns).

What causes Beta Decay?

An unstable atom with too many protons or neutrons, where protons and neutrons transform into each other to enable stability.

What are the two types of beta particles?

Positron (β+) and Negatron (β-)

What type of Beta decay releases a positron and neumino?

Excess Protons

What type of Beta decay releases -1 charge and an anti-neutrino?

Excess Neutrons