Free Essays, Term Papers, Research Papers at Anti Essays

Aim: What is a half life? What is the most recent find or discovery using half life?

Procedures:
1.) There are 5 bags in the room.
2.) You and your group will start at your assigned fossil; you have a certain amount of time at each station.
3.) In the end you can go back to a station if you must
4.) At your table open up the bag, one color puff is the isotope while the other colored puff is the decay product.
5.) Count the two and calculate the half life, record your calculations in the Report Sheet.
6.) Complete the lab questions when finished.
Data:
Report Sheet
Fossil Number Number of Parent Isotopes Number of Decay Products Number of Half Lives Age of “Fossil”
1 15 45 2 1,408 million years
2 5 35 3 2,112 million years
3 30 10 0.5 2.25 billion years
4 25 25 1 4.5 billion years
5 45 5 1/5 2.8 billion years

Formulas: Multiply the number of half lives of the element used and you get the age of the “fossil”

Questions:
1.) The fossils from oldest to youngest are 4, 5,2,1,3.
2.) 3 and 2 were very close in age.
3.) Fossil #4 came from the time just after the formation of the earth because Fossil #4 existed 4.5 billion years ago and the Earth originated 6 billion years ago.
5.) Yes, scientists can use more than one type of isotope to date the same rock or fossil because some can form around the same time and some can’t.
6.) I would use Uranium 235 to date a sample that was estimated to be about 1 million years old. I would use Uranium 235 because Uranium is used to date back fossils from millions of years ago and because uranium’s half life is closer to 1 million than Thorium 232.

Conclusion:
A half life is the time required for half of the unstable isotope to change into a stable decay product. The most recent discovery using half life is Ancient Bones found in...