The naturally occurring isotopes of Potassium are:
39 K (abundance 93.10%)
40 K (abundance 0.0118%)
41 K (abundance 6.88%)
d) What percentage of 40 K nuclei will decay in the next 10,000 years?
f) Using the definitions for the decay constant and for the becquerel, calculate the activity of 1 gram of naturally occurring potassium. (Note: 6.02 multiplied 10 '23 (i.e 1 mole) atoms of any element will have a mass in grams equal to its atomic weight, for example, 6.02 multiplied 10 '23 atoms of calcium will weigh 40.08 grams)
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