What is the empirical formula of a compound that contains 40 percent carbon, 6.7 percent hydrogen, and 53.3 percent oxygen by mass?

Which of the following is not a good technique for managing used oil? a) have specific, labeled catch pans available for technicians who are collecting oil b) spills in your shop and any releases on pavement or outside should be poured down a drain c) do not use oil containers for antifreeze or other non-similar fluids d) be prepared for oil spills with the proper absorbents

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Chlorophyll a had the molecular formula c55h72mgn4o5 how many atoms are in this molecule