Question 1
Carbon-14 has a half-life of 5715 years. Currently living organisms decay at a rate of 15.3 disintegrations/ min per gram of carbon. If an archeological artifact has a carbon-14 decay rate of 12.0 disintegrations/ min per gram of carbon, the approximate age of the artifact is ________ years old.
Question 2
Human bones found on the west coast of the United States were thought to be remains of a prospector who lived in the 19
th century. The bones were subjected to carbon-14 dating. Carbon-14 has a half-life of 5715 years. Living organisms decay at a rate of 15.30 disintegrations per minute per gram of carbon. The bones had a carbon-14 decay rate of 4.660 disintegrations per minute per gram of carbon. To one significant figure the age of the bones is ________ years old, so the person ________ (did, did not) live in the 19
th century.
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