Which one of the following is a solution?

question 21 options:

oxygen

salt water

sugar

chocolate chip cookies

which of the following is a compound?
sugar

chocolate chip cookies

oxygen

salt water

why is water considered a pure substance and not a mixture?

question 23 options:

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?

question 24 options:

filtration

crystallization

magnetic attraction

chromatography