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In a laboratory, 1.55mg of an organic compound containing carbon, hydrogen, and oxygen is burned for analysis. this combustion resulted in the formation of 1.45mg of carbon dioxide and .89 mg of water. what is the empirical formula for this compound?

How many moles of no2 will form when 3.3 moles of cu are reacted with excess hno3?

The appropriate concentration for an iodine sanitizer is