Radioactive dating practice problems Straight adult chat no registration
Some isotopes have half lives longer than the present age of the universe, but they are still subject to the same laws of quantum physics and will eventually decay, even if doing so at a time when all remaining atoms in the universe are separated by astronomical distances.Various elements are used for dating different time periods; ones with relatively short half-lives like carbon-14 (or C) are useful for dating once-living objects (since they include atmospheric carbon from when they were alive) from about ten to fifty thousand years old. Longer-lived isotopes provide dating information for much older times.Since there is now only 1/4 of the original amount of Parentium-123, we know that two half-lives of Parentium-123 have elapsed.
Given isotopes are useful for dating over a range from a fraction of their half life to about four or five times their half life.
This gives us the impression that all but a small percentage of the dates computed by radiometric methods agree with the assumed ages of the rocks in which they are found, and that all of these various methods almost always give ages that agree with each other to within a few percentage points.
Since there doesn't seem to be any systematic error that could cause so many methods to agree with each other so often, it seems that there is no other rational conclusion than to accept these dates as accurate.
Carbon-14 dating can be used on objects ranging from a few hundred years old to 50,000 years old.
Libby and others (University of Chicago) devised a method of estimating the age of organic material based on the decay rate of carbon-14.
By "age" we mean the elapsed time from when the mineral specimen was formed.