Presentation is loading. Please wait.

Presentation is loading. Please wait.

Warm Up 2/3/2014  What is nuclear radiation?  Unit Test Thursday.

Similar presentations


Presentation on theme: "Warm Up 2/3/2014  What is nuclear radiation?  Unit Test Thursday."— Presentation transcript:

1 Warm Up 2/3/2014  What is nuclear radiation?  Unit Test Thursday

2 Nuclear Radiation Video

3 Marie Curie, Nobel Prize Winner

4 What is Radioactivity?  When nuclei of unstable isotopes gain stability by undergoing changes  These reactions:  are called nuclear reactions  are always accompanied by the emission of large amounts of energy  are spontaneous  are not affected by changes in temp, pressure, or presence of catalysts  cannot be slowed down, speeded up, or turned off

5  The process by which atoms emit rays is called radioactive decay OR nuclear decay  Unstable nucleus = can be due to the overall size of the nucleus, having too many or too few neutrons  Eventually, unstable radioisotopes of one element are transformed into stable, nonradioactive isotopes of a different element

6 3 Types of Radiation  Alpha particles—positive charge, consists of helium nuclei (two protons & two neutrons)  Beta particles—negative charge, consists of fast-moving electrons formed by the decomposition of a neutron in an atom  Gamma rays—no charge, is high energy electromagnetic radiation given off by a radioisotope, have no mass, emission of these rays does not alter the atomic number or mass of an atom

7 Penetrating Ability

8

9 Example  Uranium-238 releases alpha radiation  Is transformed into another radioisotope, thorium-234

10 Example  Carbon-14 emits a beta particle as it undergoes nuclear decay, transforming into nitrogen-14  A neutron decomposes into a proton!

11 Example  Gamma rays are often emitted along with alpha or beta  Cobalt-60 shown below

12 Collaborative Group Work  Create a study tool:  On a separate sheet of paper, create a graphic organizer to compare the three types of radiation.  You should include:  Symbols  Charge  Relative mass  Penetrating power

13 Nuclear Reactions Practice

14 Homework:  Finish nuclear reactions practice sheet  Begin studying for unit test by visiting the following site to review nuclear radiation:  http://www.mdc.edu/kendall/chmphy/nuclear/types.htm http://www.mdc.edu/kendall/chmphy/nuclear/types.htm  You can also watch IsaacsTEACH and review chemistry unit 2 on youtube.

15 Warm Up 2/4/2014 What is the octet rule? How does an atom of sodium adhere to the octet rule?

16 Homework Review

17 Nuclear Fission & Fusion  Fusion = when two smaller nuclei combine or fuse  Example = hydrogen + hydrogen  helium (this occurs in the stars)  Fission = when a larger nucleus is split into lighter nuclei  Example = atom bomb or nuclear reactors, the splitting of uranium  Both types of reactions release large amounts of energy

18 Homework  Watch IsaacsTEACH 2.8 on valence electrons and Lewis structures (YouTube video)  Take notes on how to write Lewis structures  On last week’s homework, add column for Lewis structures & complete  Begin to study for your test—review notes, practice problems completed, IsaacsTEACH videos (2.1-2.9)

19 Warm Up 2/5/2014 Use the symbols for and distinguish between alpha particles, beta particles, and gamma rays.

20 Questions about Unit Test?

21 Periodic Table  Mendeleev

22

23


Download ppt "Warm Up 2/3/2014  What is nuclear radiation?  Unit Test Thursday."

Similar presentations


Ads by Google