If the short half life of carbon 14 makes it inaccurate to date artifacts that are older than 50000 years and other radioactive isotopes have longer half lives, why do scientists not use these other radioactive isotopes such as potassium-40 and uranium-235 to date an artifact?
2007-08-10 16:26:32 · 2 answers · asked by Anonymous in Science & Mathematics ➔ Chemistry
All living substances are "organic" and contain carbon. They all have a fixed ratio of C-12 and C-14. When the substance dies, the amount of C-14 present decays at a known rate. So it is possible to calculate the age of death by observing how much C-14 is still present.
Other radioactive isotopoes do not play a role in life forms as carbon does.
2007-08-10 16:40:18 · answer #1 · answered by reb1240 7 · 0⤊ 0⤋
How many artifacts contain uranium? And the problem with potassium is that its salts are soluble -- so they're not usually still around after thousands of years. Carbon is plentiful in the types of artifacts that are usually found. That's the main reason.
2007-08-10 16:36:19 · answer #2 · answered by Fly On The Wall 7 · 0⤊ 0⤋