Topic: Nuclear Chemistry Aim: What are real examples of artificial transmutations? Do Now: compare and contrast natural and artificial transmutations. HW: text p. 891 #18-23

Nuclear Energy Mass is converted into energy Energy yield is approx. 10 million times the energy released when the same amt of a fossil fuel is burned!

Nuclear Power 441 nuclear power plants in 32 countries Supply ~21.2% of world's electricity Energy released is 10 million times greater than energy released from burning 1 atom of carbon from a fossil fuel 1 gram of Uranium has energy equivalent to approximately 3 tons of coal. We need to consume about 3 million times less material with Nuclear Power compared to using Coal or any other fossil fuel

Power plants in US & years of operation From Nuclear Regulatory Commission, 2011

Source: Clean and Safe Energy Coalition Nuclear Power in NYS Source: Clean and Safe Energy Coalition

Indian Point Power Plant

Nuclear Power Plant Purpose: generate heat, boil water to produce electricity NPPs (& burning fossil fuels) convert water to steam Steam spins blades of a turbine  spins shaft of generator. Inside generator, coils of wire and magnetic fields interact to create electricity.

Reactor Fuel Assembly Uranium radioisotopes formed into fingertip-sized pellets Pellets inserted into long fuel rods in the reactor 50-200 fuel rods per assembly, 120-900 assemblies per reactor with spaces between them for water to flow Fuel Rod

Nuclear Reactor Heart of power plant Where water is heated 4 parts Fuel assemblies (contain Uranium) Control rods Coolant/moderator (water) Pressure vessel From last slide

Nuclear Reactor Can’t throw Uranium into reactor like coal into a furnace. Uranium undergoes FISSION, which produces smaller, more stable nuclei & what other particles? Neutrons These can then collide with other Uranium nuclei, fueling a chain reaction FISSION

Chain Reaction Splitting nuclei generate HEAT inside fuel assembly Heats water in pressure vessel Water turns to steam, passes to steam generator

Nuclear Reactor These reactions generate a LOT of heat Cooled by water in the pressure vessel What if temp gets too high? What if reaction progresses too quickly?

Nuclear Reactor Control rods Made of boron carbide, silver, indium, cadmium, or hafnium Job is to absorb excess neutrons produced during fission This SLOWS or STOPS the chain reaction!

Control Rods Rods will slide between fuel assemblies in varying degrees to absorb excess neutrons, slowing the reaction & regulating temperature http://phet.colorado.edu/en/simulation/nuclear-fission

Generator Steam generator builds pressure, steam turns blades of turbine Wire coils & magnets interact to generate electricity

Nuclear Reactor

FYI On a cross-country flight, you will receive an average of 3-5 millirems of radiation. This is more than you would receive standing at the gate of a nuclear power plant 24 hours a day for a year.   (Source: DOE) The energy in one uranium fuel pellet – the size of the tip of your little finger – generates the same amount of electricity as 1,780 pounds of coal, 149 gallons of oil, and 17,000 cubic feet of natural gas.

What happened in Japan? CNN 3 minutes http://www.youtube.com/watch?v=BdbitRlbLDc vlog brothers 7 minutes http://www.youtube.com/watch?v=rBvUtY0PfB8 rachel maddow explaining function of nuclear power plants in simple terms! (re: japan in march) http://www.youtube.com/watch?v=XibS-W_loJ0  (13 minutes) another rachel maddow - showing model of fuel rods - again, easy to understand. http://www.youtube.com/watch?v=zB54o8Id4R4&feature=relmfu (13 minutes)  rachel maddow - 15 minutes http://www.youtube.com/watch?v=RiXIODVlfXk&feature=related