Water is a substance. If you put it together with something soluble, it becomes a solution. With something non-soluble, it becomes a mixture.
alcohol and water
Substance is not a sharply differentiated word. Kerosene and water would are a mixture (to the extent that they will mix), but they could also be termed a substance as mixtures can be substances under some uses of the word substance. However mixtures can be differentiated from solutions and compounds -- kerosene and water is not a solution nor a compound.
Strictly, water itself is a pure substance, but most of the samples of water we meet are mixtures. De-ionized water which we use in the lab is water and nothing else (pure). Tap water and natural samples from the world around us contain dissolved substances from the air and the rocks, so they are mixtures.
Mixtures: can be separated by physical means
No they are mixtures
somewhat... in mixture, the solvent dissolves into the solute. in substance, the solvent merely mixes with the solute. for example, salt in water is a substance. the salt mixes with the water.
Yes, water (as a liquid, solid or gas) can be obtained as a pure substance; but frequently water contain many impurities.
what is mixtures
The two main branches are pure substances and mixtures.
The aqueous state refers to a substance that is dissolved or suspended in water. It is commonly used to describe solutions or mixtures where water is the solvent.
no
if a substance is a mixture then it is heterogeneous.