18 terms

10.1 Radioactivity

The process in which an unstable atomic nucleus emits charged particles and energy.
Any atom containing an unstable nucleus (radioactive isotope)
Nuclear Radiation
charged particles and energ that are emited from the nuclei of radioisotopes.
Alpha Particle
a positively charges particle made up of two protons and two neutrons.
Beta Particle
an electron emitted by an unstable nucleus.
Gamma Ray
a penetrating ray of energy emitted by an unstable nucleus.
Background Radiation
nuclear radiation that occurs naturally in the environment
What devices can detect nuclear radiation?
Devices that are used to detect nuclear radiation include Geiger counters and film badges.
How does nuclear radiation affect atoms?
Nuclear radiation can ionize atoms.
What are 3 types of nuclear radiation?
Common types of nuclear radiation include alpha particles, beta particles, and gamma rays.
What happens during nuclear decay?
During nuclear decay, atoms of one element can change into atoms of different element altogether.
I. Nuclear Decay
Radioisotopes of uranium--primarily uranium-238--were the source of radioactivity in Becquerel's experiment.
Radioisotopes spontaneously change into other isotopes over time.
II. Types of Nuclear Decay
Scientists can detect a radioactive substance by measuring the nuclear radiation it gives off.
A. Alpha Decay
common symbol -> He-4
Alpha particles are made up of two protons and 2 neutrons.
Stopped by sheet of paper or clothing.
B. Beta Decay
Beta particles are electrons emitted by an unstable nucleus.
Written as 0^ -1e
atomic number: -1
Made up one more proton and one less neutron.
Stopped by thin sheet of metal
C. Gamma Decay
Penetrating ray of energy.
No mass and no charge
Atomic number and mass number dont change but energy decreases.
Stopped by lead or concrete
III. Effects of Nuclear Radiation
When nuclear radiation exceeds background levels, it can damage the cells and tissues of your body.
IV. Detecting Nuclear Radiation
A Geiger counter detects nuclear radiation by using a gas-filled tube to measure uonizing radiation since nuclear radiation can ionize atoms.
The greater the amount of nuclear radiation, the greater the electric current produceed in the tube is.