Term 2 Week 5 2016

Homework

• Ex 5A, P. 151-155, Models of the Atom

Parts of the Atom

Isotopes

Isotopes are versions of an atom or an element that have the same number of protons, but different numbers of neutrons

Radioactive Decay

Alpha, Beta & Gamma Radiation

• Alpha particles are emitted by a larger nucleus that has too many Protons
• Beta particles are emitted by a nucleus that has too many Neutrons
• Gamma photons are emitted by a nucleus that has too much Energy (is in an exited state)

• PhET Alpha Decay app can be found here
• PhET Beta Decay app can be found here

Alpha Decay

Beta Decay

Radiation

Types of Radiation

Half-Life

Half-Life Explanation

Half-Life Calculations

Half-Life Formula

A = Ao(½)n

A: Amount of radioactive substance now present

Ao: Amount of radioactive substance originally present

n: Number of Half-Lives that have past

If you can understand the maths for using the formula above, you will be able to pinpoint your answers instead of estimating them using a graph.

You will need to be able to use the 3rd Log Law to solve for half lives.