see eye to eye (with someone) - definition and synonyms. Close. 90% of the time, speakers of English use just 7,500 words in speech and writing. These words appear in red, and are graded with stars. One-star words are frequent, two-star words are more frequent, and three-star words are the most frequent.
Iodine, in the form of iodide, is made into two radioactive isotopes that are commonly used in patients with thyroid diseases: I-123 (harmless to thyroid cells) and I-131 (destroys thyroid cells).odine, in the form of iodide, is made into two radioactive isotopes that are commonly used in patients with thyroid diseases: I-123 (harmless to thyroid cells) and I-131 (destroys thyroid cells).
Different isotopes have different half-lives and sometimes more than one present isotope can be used to get an even more specific age of a fossil. Below is a chart of commonly used radiometric isotopes, their half-lives, and the daughter isotopes they decay into. Example of How to Use Half-Life. Let's say you have found a fossil you think to be a human skeleton. The best radioactive element to use to date human fossils is Carbon-14.