Oxygen-16 and Carbon-12 are stableisotopes of elements O and C respectively. Hence, they do not have half-lives. But Carbon-14 andUranium-238 are radioactive isotopes. Among them Carbon-14 has relatively short half-life as about 5730 years while Uranium-238 has a long half-life as about 4.5 billion years.
Answer is. uranium-238
Answer;
-Analytical chemistry - composition.
Environmental - impact of chemicals
Explanation;
-Analytical chemistry involves the qualitative and quantitative determination of the chemical components of substances. In qualitative analysis all the atoms and molecules present are identified, with particular attention to trace elements. In quantitative analysis the exact weight of each constituent is obtained as well.
Environmental chemistry is the study of the chemical and biochemical phenomena that occur in the environment.It relies heavily on analytical chemistry and includes atmospheric, aquatic, and soil chemistry.
They are called transmission electron microscopes.
