28.1

633 views
581 views

Published on

0 Comments
1 Like
Statistics
Notes
  • Be the first to comment

No Downloads
Views
Total views
633
On SlideShare
0
From Embeds
0
Number of Embeds
18
Actions
Shares
0
Downloads
22
Comments
0
Likes
1
Embeds 0
No embeds

No notes for slide

28.1

  1. 1. Ch 28.1 Nuclear Radiation
  2. 2. Radioactivity <ul><li>Nuclear reaction- radioisotopes undergo “decay” into stable isotopes ( which don’t decay ) </li></ul><ul><li>Nuclear reactions release lots of energy </li></ul><ul><li>Not affected by pressure, temp, catalysts- cannot be sped up, slowed down or stopped </li></ul>
  3. 4. Radioactivity <ul><li>Henri Bequerel showed Uranium salts fogged up photo plates- gave off what was later known as radiation </li></ul><ul><li>Marie and Pierre Curie- isolated the radioactive substances ( discovered new elements in process) and found “rays” were emitted which caused this radiation and termed it radioactivity </li></ul>
  4. 5. Radioactivity <ul><li>This process of unstable nuclei emitting radiation and eventually forming stable nuclei has to do with a neutron:proton ratio that is greater than or less than 1 (there are either more neutrons or fewer neutrons than there are protons) </li></ul><ul><li>Radioactive decay is spontaneous </li></ul>
  5. 6. Types of Radiation <ul><li>3 types- alpha, beta, gamma </li></ul><ul><li>Rutherford experiment </li></ul>
  6. 10. Alpha <ul><li>He nulcei </li></ul><ul><li>+2 charge </li></ul><ul><li>Stopped by paper or skin </li></ul><ul><li>Nuclear equation for alpha decay: </li></ul>
  7. 11. Beta <ul><li>Electron ( from a neutron breaking down into a proton and a electron) from the nucleus </li></ul><ul><li>-1 charge </li></ul><ul><li>Can be stopped by aluminum foil </li></ul><ul><li>Nuclea equation fro beta decay: </li></ul>
  8. 12. Gamma <ul><li>Hi energy electromagnetic radiation </li></ul><ul><li>Not a particle </li></ul><ul><li>Most dangerous </li></ul><ul><li>Can be partially stopped by thick concrete and lead </li></ul><ul><li>Often emitted with alpha and beta decay </li></ul><ul><li>Nuclear equation: </li></ul>
  9. 15. X-rays <ul><li>Are a type of electromagnetic radiation </li></ul><ul><li>Not gamma rays </li></ul><ul><li>Comes from excited electrons; not from nuclear decay </li></ul>
  10. 16. How does radioactive decay hurt Dalton’s atomic theory?

×