Seudónimo Seudónimo 02-11-2016 Chemistry contestada Which one of the following is a compound? sugar chocolate chip cookies oxygen salt water Why is water considered a pure substance and not a mixture? Water can be separated physically into hydrogen and oxygen. Water is clear. Water can be separated chemically into hydrogen and oxygen. Water is not a pure substance. It is a mixture. How can a mixture of pigments be separated? filtration crystallization magnetic attraction chromatography