Half Life Practice
If you only have 9.375g of the U-238 left in a sample that used to be 75g of U-238, how old is this sample? (Half life of U-238 is 4.46 billion years). (ans 13.38 billion years)
If you started with a sample of C-14 that had a mass of 58g, how many years have gone by when the sample only contains 1.8125g of C-14? (Half life of C-14 is 5,730 years.) (ans 28,650 years)
If six half lives go by for a sample of Actinium 225, how long has it been? (Half life of Actinium-225 is 10 days). (ans 60 days)
If I only have 3.125% of the antimony 124 left in a sample, how old is the sample? (half life of antimony-124 is 60.2 days). (ans 301 days)
If you start with 36g of U-238, and you end up with 2.25g of U-238, how much time has gone by? (Half life of U-238 is 4.46 billion years). (ans 17.84 billion years)
Hosted by 