7D10.15 - Isotopes

Pre-1982 pennies have a mass of about 3.10 grams.  The post-1983 pennies will have a mass of about 2.51 grams.  Place some of each kind of penny into a container and weigh.  Formulate a procedure to determine the amount of each isotope present.
Code Number:
7D10.15
Demo Title:
Isotopes
Condition:
Excellent
Principle:
Elemental Isotopes
Area of Study:
Modern Physics
Equipment:
Pre-1982 pennies, post-1983 pennies
Procedure:

Pre-1982 pennies have a mass of about 3.10 grams.  The post-1983 pennies will have a mass of about 2.51 grams.  Place some of each kind of penny into a container and weigh.  Formulate a procedure to determine the amount of each isotope present. 

References:
  • B. Cameron Reed, "Neutrons as Party Animals: An Analogy for Understanding Heavy-Element Fissility, TPT, Vol. 50, #9, Dec. 2012, p. 544.
  • Ralph E. Weston, Jr., "A Boatload of Pennies",  TPT, Vol. 40, #7, Oct. 2002, p. 392.
  • Haym Kruglak, "Watch Your Pennies! - A Correction", TPT, Vol. 29, #5, May 1991, p. 262.
  • Terrence P. Toepker, "More Physics Cents", TPT, Vol. 29, #8, Nov. 1991, p. 484.
  • E. Scott Barr, "The Masses of Coins", TPT, Vol. 21, #6, Sept. 1983, p. 348.
  • R.D. Edge, "The Author Replies: It's Not Simple", TPT, Vol. 21, #6, Sept. 1983, p. 348.
  • Toni Feder, "Isotope Program Expands Activities", Physics Today, Vol. 68, #10, Oct. 2015, p. 20.
  • Johanna Miller, "Isotope Ratios Hint at a Piece of Pristine Earth", Physics Today, Vol. 63, #10, Oct. 2010, p. 16.
  • Phillip M. Walker and James J. Carroll, "Ups and Downs of Nuclear Isomers", Physics Today, Vol. 58, #6, June 2005, p. 39 - 44. 
  • William McNairy, "Baffling Buoyancy", 2008 AAPT/PIRA Apparatus Competition, An Entry for the Low Cost Category. 
  • Ramsey O. Benavides, "Independent Project: Two Chemistry Experiments on the Subject of Atomic Structure", Apr. 1996.

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