2. Chapter 28: Nuclear Chemistry Nuclear Chemistry… I. Nuclear Radiation II. Radioactive Decay III. Nuclear Reactions IV. Nuclear Applications and Effects….

3. The Discovery of Radioactivity Heinrich Hertz proved the existence of radio waves in 1890.Heinrich Hertz proved the existence of radio waves in 1890. German physicist Wilhelm Roentgen found that invisible rays were emitted by some minerals in 1895…he called these x-rays.German physicist Wilhelm Roentgen found that invisible rays were emitted by some minerals in 1895…he called these x-rays. French physicist Henry Becquerel discovered that some minerals glowed when exposed to light…he also worked with the minerals Roentgen discovered and extended on his work….Marie and Pierre Curie took the, pitchblende, and Marie named the process radioactivity….Becquerel and the Curies shared the 1903 Nobel peace prize for their work with ‘radioactivity’.French physicist Henry Becquerel discovered that some minerals glowed when exposed to light…he also worked with the minerals Roentgen discovered and extended on his work….Marie and Pierre Curie took the, pitchblende, and Marie named the process radioactivity….Becquerel and the Curies shared the 1903 Nobel peace prize for their work with ‘radioactivity’.

4. Nuclear Particles Alpha particleAlpha particle Beta particleBeta particle Gamma particleGamma particle 4 2He  β

5. Alpha Decay Alpha particles are a helium nucleus with a +2 charge and a mass of 4 amu…Alpha particles are a helium nucleus with a +2 charge and a mass of 4 amu…

6. Beta Decay Beta particles are fast moving electrons with no mass and -1 charge…Beta particles are fast moving electrons with no mass and -1 charge…

7. Gamma Decay Gamma radiation is like light and energy from an explosion…it occurs with alpha or beta decay as a secondary product.Gamma radiation is like light and energy from an explosion…it occurs with alpha or beta decay as a secondary product.

8. Nuclear Stability Transmutation is the conversion of one atom to another type by changing the nucleus.Transmutation is the conversion of one atom to another type by changing the nucleus. Protons and neutrons are referred to as nucleons.Protons and neutrons are referred to as nucleons. The strong nuclear force acts on nuclear particles that want to push away from each other and causes them to stay together.The strong nuclear force acts on nuclear particles that want to push away from each other and causes them to stay together. Neutron to proton ration, for elements of < 20 atomic # is 1:1…above that, there are more neutrons than protons.(see pg 866)Neutron to proton ration, for elements of < 20 atomic # is 1:1…above that, there are more neutrons than protons.(see pg 866)

9. Nuclear Stability The area of a nuclear stability graph, that is a plot of stable nuclei, is called the band of stability.The area of a nuclear stability graph, that is a plot of stable nuclei, is called the band of stability. Different decays occur based upon the graph location of the radioisotope…Different decays occur based upon the graph location of the radioisotope… Directly off the end of the band of stability isotopes undergo alpha decay.Directly off the end of the band of stability isotopes undergo alpha decay. Left and above the band, isotopes undergo beta decay.Left and above the band, isotopes undergo beta decay. Below and right isotopes undergo positron emission.Below and right isotopes undergo positron emission.

10. Nuclear Stability See Pg 866

11. Beta Absorption or Positron Emission

12. Nuclear Particles Alpha particleAlpha particle Beta particleBeta particle Gamma particleGamma particle 4 2He  β

13. Penetration Power

14. Nuclear Fission Nuclear Fission is the reaction used to power submarines, aircraft carriers, and nuclear power plants.Nuclear Fission is the reaction used to power submarines, aircraft carriers, and nuclear power plants. Fission is the splitting of atoms into 2 smaller nuclei.Fission is the splitting of atoms into 2 smaller nuclei.

15. Nuclear Reactions Nuclear Fusion Nuclear Fusion… Combining of 2 smaller nuclei to make one larger nucleus.Nuclear Fusion… Combining of 2 smaller nuclei to make one larger nucleus. We cannot conduct nuclear fusion to produce energy because it requires too much energy input and too much hear.We cannot conduct nuclear fusion to produce energy because it requires too much energy input and too much hear.

16. Detecting Radiation Gieger counters count electron strikes in a gas tube.Gieger counters count electron strikes in a gas tube. Scintilation counters count electron strikes to a phosphorescent screen.Scintilation counters count electron strikes to a phosphorescent screen. Film ID badges are worn by employees and analyzed at night or at the end of the week to see radiation strikes.Film ID badges are worn by employees and analyzed at night or at the end of the week to see radiation strikes.