Presentation on theme: "NUCLEAR CONCEPTS in EARTH SCIENCE & PHYSICAL SCIENCE."— Presentation transcript:
NUCLEAR CONCEPTS in EARTH SCIENCE & PHYSICAL SCIENCE
KENTUCKY CORE CONTENT for ASSESSMENT in High School Science
BIG IDEA: EARTH AND THE UNIVERSE (Earth/Space Science)
SC-HS-2.3.3 SC-HS-2.3.3 Students will explain the origin of heavy elements in planetary objects (planets & stars)
SC-HS-2.3.4 SC-HS-2.3.4 Students will understand that stars generate energy from nuclear fusion reactions that create successively heavier chemical elements.
SC-HS-2.3.6 SC-HS-2.3.6 Students will compare the limitations/ benefits of various techniques for estimating geologic time (radioactive dating, observing rock sequences, and comparing fossils).
BIG IDEA: ENERGY TRANSFORMATIONS (Unifying Concepts)
SC-HS-4.6.8 Students will: describe the connections between the functioning of the Earth system and its sources of energy (internal and external) predict consequences of changes to any component of the Earth system
SC-HS-4.6.11 Students will: explain the difference between alpha and beta decay, fission, and fusion; identify the relationship between nuclear reactions and energy.
SC-HS-4.6.12 Students will understand that the forces that hold the nucleus together, at nuclear distances, are usually stronger than the forces that would make it fly apart.
Lessons 1-2 Absolute-Age Dating of Rocks (2.3.6 & 4.6.8) OBJECTIVES: Explain several different methods used by scientists to determine absolute age of rocks. Explain several different methods used by scientists to determine absolute age of rocks. Define isotopes. Define isotopes. Describe how objects are dated by the use of certain radioactive elements. Describe how objects are dated by the use of certain radioactive elements. Describe the evidence used to determine the age of the Earth. Describe the evidence used to determine the age of the Earth.
Objectives: Describe the processes of nuclear fission and fusion. Trace the events in a nuclear chain reaction and explain the origin of the energy released. Explain how energy from fission is converted to electricity in a nuclear reactor. Describe the parts of a nuclear reactor.
The Gold Leaf Electroscope The Gold Leaf Electroscope When an electroscope is charged, the gold leaf sticks out, because the charges on the gold repel like charges on the metal rod. When an electroscope is charged, the gold leaf sticks out, because the charges on the gold repel like charges on the metal rod. When a radioactive source comes near, the air is ionized, and starts to conduct electricity. This means that the charge can "leak" away, the electroscope discharges and the gold leaf falls.
Geiger Counter This is actually a Geiger-Müller tube with some form of counter attached, which usually tells us the number of particles detected per minute ("counts per minute"). Geiger-Müller GM tubes work using the ionizing effect of radioactivity. ionizing
Cloud Chamber The chamber contains a supersaturated vapor which condenses into droplets when disturbed and ionized by the passage of a particle. The droplets form a trail in the chamber.
Photographic Film In 1896, Henri Becquerel discovered that uranium compounds would darken a photographic plate, even if the plate were wrapped up so that no light could get in. Becquerel The amount of fogging or darkening is determined by how much radiation strikes the film.
Photographic Film Workers in the nuclear industry wear "film badges" which are then developed. This allows for the measurement of the dose that each worker has received. This allows for the measurement of the dose that each worker has received.
Objective 2 Describe the use of radioisotopes in: studying organisms studying organisms diagnosing and treating disease diagnosing and treating disease sterilizing food sterilizing food monitoring industrial processes monitoring industrial processes
Radioactive Dating Animals and plants have a known proportion of carbon-14 in their tissues. When they die, the amount of C-14 goes down at a known rate. Since C-14 has a half-life of about 5700 years, the age of ancient organic materials can be found by measuring the amount of C-14 that is left.
Radioactive Tracers Radioisotopes are frequently used as tracers whose pathways through the steps of chemical reactions may be traced. These may be used for medical purposes such as checking for blockages or circulatory problems.
Cancer Treatments Because gamma rays can kill living cells, they are used to kill cancer cells without having to resort to difficult surgery. This is called radiation therapy and works because cancer cells cannot repair themselves when damaged as healthy cells can.
Sterilizing Even after it has been packaged, gamma rays can be used to kill bacteria, mould and insects in food. This process prolongs the shelf-life of the food. Gamma rays are also used to sterilize hospital equipment, especially plastic syringes that would be damaged if heated
Industrial Processes Radioisotopes may be used in industry to detect leaking pipes. To do this, a small amount is injected into the pipe. It is then detected with a GM counter above ground. Radioisotopes may be used in industry to detect leaking pipes. To do this, a small amount is injected into the pipe. It is then detected with a GM counter above ground. Checking welds: a gamma source is placed on one side of the welded metal and a photographic film on the other side. Weak points or air bubbles will show up on the film, like an X-ray.
WORKSHEETS Estimate Your Personal Radiation Dose Atomic Crossword (NRC website) Test Your Nuclear Knowledge Quiz (NRC website)
LAB ACTIVITY Radiation and Shielding Radiation and Shielding
OPEN RESPONSE QUESTIONS Radioactive Decay Radioactive Dating Carbon Dating
MEDIA ITEMS Videos: A Look at Radiation and Managing Radiation ( a free kit from The National Safety Council: http://www.nsc.org/issues/radisafe.htm) Website of Nuclear Regulatory Commission: http://www.nrc.gov/reading- rm/basic-ref/students.html (student activities) http://www.nrc.gov/reading- rm/basic-ref/students.htmlhttp://www.nrc.gov/reading- rm/basic-ref/students.html
GOING FURTHER Obtain a radon test kit and test your home for the presence of radon gas. (These may be obtained free-of-charge from some local health departments.) (These may be obtained free-of-charge from some local health departments.)
GOING FURTHER Observe radiation flashes by looking at a Fiestaware plate through a magnifying glass in a totally dark room. (First allow a few minutes for your eyes to adjust to the darkness.) (First allow a few minutes for your eyes to adjust to the darkness.)