Which is the best description of a chain of custody? a) a list of all personnel entering the crime scene. b) a log of which family member has ownership of the evidence. c) a log of which agency controls the evidence so the case stays in the correct jurisdiction. d) a log of who has handled the evidence and when so the integrity of the evidence is upheld.

Determine the empirical formula of a compound containing 40.6 grams of carbon, 5.1 grams of hydrogen, and 54.2 grams of oxygen. in an experiment, the molar mass of the compound was determined to be 118.084 g/mol. what is the molecular formula of the compound? for both questions, show your work or explain how you determined the formulas by giving specific values used in calculations.

18. use the activity series to predict whether the following synthesis reaction will occur. write the chemical equations for the reaction if it's predicted to occur. (s) + o2(g) -> *note: it is possible.*

How many moles are in 250 grams of tungsten (w)? * 4.4x10^23 moles 4.2x10^23 moles 0.7 moles 1.4 moles