if you have 30% of 100 milliliters of an aqueous solution of ethanol, what volumes of ethanol and water are in the solution?

Volumes of ethanol and water are in the solution : 30 mL and 70 ml

The concentration of a substance can be expressed in several quantities such as moles, percent (%) weight/volume,), molarity, molality, parts per million (ppm) or mole fraction. The concentration shows the amount of solute in a unit of the amount of solvent.

Percent Volume (% v/v) : volume (ml) of solute/100 ml of solution ⇒ ratio of volume of the solute to total volume of the solution

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30% ethanol ⇒30% etanol, 70% water

In 100 mL solution :

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