Radiometric dating uses what isotopes
The radiocarbon age of a certain sample of unknown age can be determined by measuring its carbon 14 content and comparing the result to the carbon 14 activity in modern and background samples.
The principal modern standard used by radiocarbon dating labs was the Oxalic Acid I obtained from the National Institute of Standards and Technology in Maryland. Around 95% of the radiocarbon activity of Oxalic Acid I is equal to the measured radiocarbon activity of the absolute radiocarbon standard—a wood in 1890 unaffected by fossil fuel effects.
Liquid scintillation counting is another radiocarbon dating technique that was popular in the 1960s.
In this method, the sample is in liquid form and a scintillator is added.
Thorium is commercially recovered from the mineral monazite and occurs also in other minerals such as thorite and thorianite.
Thorium metal has been produced in commercial quantities by reduction of the tetrafluoride (Th F Thorium, also, is potentially of great economic value, because one of its isotopes, thorium-232, can be converted into the fissionable isotope uranium-233 in a nuclear breeder reactor (i.e., one that produces more fissionable material than it consumes), thus increasing by many times available supplies of…
The metal may be extruded, rolled, forged, swaged, and spun, but drawing is difficult because of thorium’s low tensile strength.
A vial with a sample is passed between two photomultipliers, and only when both devices register the flash of light that a count is made.Thorium is added to magnesium and magnesium alloys to improve their high-temperature strength.It has been used in commercial photoelectric cells for measuring ultraviolet light of wavelengths ranging from 2000 to 3750 angstroms.Over the years, carbon 14 dating has also found applications in geology, hydrology, geophysics, atmospheric science, oceanography, paleoclimatology and even biomedicine.Radiocarbon, or carbon 14, is an isotope of the element carbon that is unstable and weakly radioactive. Carbon 14 is continually being formed in the upper atmosphere by the effect of cosmic ray neutrons on nitrogen 14 atoms.