PLEASE HELP 100 POINTS
IF YOU KNOW CHEMISTRY OR BIOLOGY

Iwll give extra points to who gets this for ! what type of reaction is this? ?

Harvey mixes two liquids. which observation of the new mixture most likely indicates a precipitate is forming?

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?