Naked Science Forum

Non Life Sciences => Chemistry => Topic started by: Cammy34349 on 24/06/2021 14:24:28

Title: Can elements contain multiple isotopes within one sample?
Post by: Cammy34349 on 24/06/2021 14:24:28
Hey, Studying for my GCSEs at the moment (uk high school exams), and have been trying to figure out something about isotopes but my teachers are all on holiday :(     I'm sure to most of you this is a very basic question, but to me help would be greatly appreciated :))

when it comes to isotopes, can a certain element e.g. a block of zinc, contain multiple isotopes within that sample, like is a block of carbon-13 called carbon-13 because it only contains that isotope OR is it because when balancing out that particular isotope it ends up at that isotope (some Carbon-12 and some Carbon-14)
Title: Re: Can elements contain multiple isotopes within one sample?
Post by: Janus on 24/06/2021 14:51:51
Any random sample of an element can contain a number of isotopes.  For example, Uranium in its natural form is made up of both U-238 and U-235.  Since only U-235 is fissile, "raw" Uranium has to be enriched (The percentage of U-235 increased) in order for it to be useful for power plants or nuclear weapons(Nuclear weapons need a much higher enrichment than reactor fuel needs)
Title: Re: Can elements contain multiple isotopes within one sample?
Post by: evan_au on 25/06/2021 10:43:33
If you look up the isotopes of an element in Wikipedia, you will see a typical abundance in nature for the common isotopes.

They also provide a larger table that includes all the isotopes that are too unstable to have any measurable concentration in nature.

See, for example Oxygen, which has 3 stable isotopes in nature, and 13 unstable isotopes which have been studied.
https://en.wikipedia.org/wiki/Isotopes_of_oxygen
Title: Re: Can elements contain multiple isotopes within one sample?
Post by: alancalverd on 25/06/2021 12:01:50
The standard Periodic Table lists the mean atomic weight of naturally-occuring elements. There are several decimal points in all entries because the natural or chemically refined material rarely consists of a single isotope - you need to do some additional physics to separate them.