_29) Half-Life Problems

Front

The diagram shows 32 atoms. The Red are parent isotopes, and the Green are daughter isotopes. How many half-lives have occurred?

Back

1

Front

The diagram shows 32 atoms. 32 of the Red are the parent isotope. How many half-lives have occurred?

Back

0

Front

What is the Half life of this isotope?

Back

10 seconds

Front

What is the Half Life of this isotope?

Back

3 days

Front

After 22,800 years, approximately what percentage of the original carbon-14 remains?

Back

6.25%

Front

How many more years will it take to have 0.625 grams of strontium-90?

Back

29 years

Front

Approximately how long would it take for 25 potassium atoms to decay starting with an original sample size of 100?

Back

0.64 billion years

Front

Uranium-235 decays into lead-207 with a half life of 704 million years. A sample of granite contains 12.5% uranium-235 and 87.5% lead-207. How old is the granite rock?

Back

2.1 billion years

Front

Barium-122 has a half-life of 2 minutes. A fresh sample weighing 80 g was obtained. If it takes 10 minutes to set up an experiment using barium-122, how much barium-122 will be left when the experiment begins?

Back

2.5g

Front

Fermium-253 has a half-life of 0.334 seconds. How much time will elapse for this sample to be considered completely decayed after 10 half-lives?

Back

3.34 seconds