Radioactivity Flashcards
Who discovered radioactive atoms
Henri Becquerel
What happens in the nucleus of radioactive atom
The nucleus is unstable so to make it stable it emits a radioactive particle or a wave
Who discovered electrons
JJ Thompson but he suggested that all particles in an atom were mixed together this is called the plum pudding model
What did Rutherford discover
That most of the particle in an atom were held in a central nucleus
What is an isotope
An atom that has an uneven amount of neutrons
What are elections attracted to the nucleus by
An electrostatic force
What can happen when an atom absorbs energy
It can move up an electron shell( to an excited state)
How can a electron move down a shell
It can release excess energy as a photon
Name three natural sources of radiation
Cosmic rays, rocks and soil and living things
How have humans added to background radiation
Radioactive waste, radioactive fall out ( weapon testing ) and medical exposure
How do we measure radiation
With a Geiger counter
What is the structure of alpha
2 protons and 2 neutrons
What happens when a atom decays
It forms a daughter atom and releases radiation
