Dating radioactive elements

The recognition that the rate of decay of any radioactive parent atom is proportional to the number of atoms () of the parent remaining at any time gives rise to the following expression: Converting this proportion to an equation incorporates the additional observation that different radioisotopes have different disintegration rates even when the same number of atoms are observed undergoing decay.

C and counting the amount of each) allows one to date the death of the once-living things.

Perhaps you have heard of Ice Man, a man living in the Alps who died and was entombed in glacial ice until recently when the ice moved and melted.

By way of explanation it can be noted that since the cause of the process lies deep within the atomic nucleus, external forces such as extreme heat and pressure have no effect.

The same is true regarding gravitational, magnetic, and electric fields, as well as the chemical state in which the atom resides.

In fact, one would expect that the ratio of oranges to apples would change in a very specific way over the time elapsed, since the process continues until all the apples are converted. A particular rock or mineral that contains a radioactive isotope (or radio-isotope) is analyzed to determine the number of parent and daughter isotopes present, whereby the time since that mineral or rock formed is calculated.

Of course, one must select geologic materials that contain elements with long half-lives— those for which some parent atoms would remain.Given below is the simple mathematical relationship that allows the time elapsed to be calculated from the measured parent/daughter ratio.The age calculated is only as good as the existing knowledge of the decay rate and is valid only if this rate is constant over the time that elapsed.The man's body was recovered and pieces of tissue were studied for their C content by accelerator mass spectroscopy.The best estimate from this dating technique says the man lived between 33 BC. From the ratio, the time since the formation of the rock can be calculated.The situation is analogous to the death rate among human populations insured by an insurance company.

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