one of the decay products of 238u is 226ra . a rock originally contained 238u , which has a half-life of 4.5×10^9 yr, and 226ra , which has a half-life of 1,600 yr. after 5×10^9 yr, which isotopes would you expect to be present in significant amounts in the rock?

An atom of lithium (li) and an atom of chlorine (cl) engage in a chemical reaction. which correctly describes the structure of the resulting chemical compound? hint: consider the class of each element. the chemical compound will have a network structure. the chemical compound will have triple bonds. the chemical compound will have a ball-and-stick structure. the chemical compound will have double bonds.

650.j is the same amount of energy as? 2720cal1550cal650.cal2.72cal

Why is it possible for different microorganisms to extract energy not only from carbohydrates and other biological molecules but from a large variety of substances?