Atomic Structure & Periodic Table, Radioactivity Flashcards
Protons have a _____ charge and are found?
Positive, in the nucleus
What charge do electrons have? And where do you find them?
Negative, around the necleus
Which subatomic particle has no charge?
Neutrons
The atomic number of an element = the number of ______ in the nucleus of an atom of the element?
Protons
True of false, the mass number is always the bigger number compared with the atomic number?
True - mass number is the total number of particles in the nucleus of an atom.
Atoms are composed of?
Protons, neutrons and electrons
A whole atom is always neutral; therefore the total number of ______ always equals the number of _______.
Electrons and protons
Define the term isotope
Atoms of the same element with different masses (due to differing numbers of neutrons)
If two atoms have different mass numbers but the same atomic number they are called?
Isotopes
A radioactive isotope or radioisotope is when?
An atom with an unstable nucleus that spontaneously decays and emits radiation until the nucleus become stable
What are the 3 main types of radiation?
Alpha, Beta, Gamma
Radiation that is pure energy, has no charge, can travel up to 2km, go right through skin and is stopped by thick lead or concrete is called?
Gamma radiation
Alpha radiation sends 2 _____ & 2 ______ out from the nucleus, creating a different element
protons, neutrons
Which radiation has a -1 charge, can travel a few metres, penetrate the skin a few mm and is stopped by wood or metal sheets?
Beta radiation
Describe the effects of direct radiation on a cell
Alpha or Beta collide with the cells causing them to break. Damage means the cell cannot repair itself so it dies. Damage to DNA can cause mutations when cells divide, possibly leading to cancer
