A particulate diagram represents an ethanol–water mixture prepared by combining equal…
CHEMISTRY · Single correct · AP · Chemistry · Properties of Substances and Mixtures · Properties of Substances and Mixtures
Problem
A particulate diagram represents an ethanol–water mixture prepared by combining equal masses of ethanol and water. The box contains 55 water molecules and 30 ethanol molecules. Which of the following best identifies the solvent in the diagram and justifies that choice?
(a) Ethanol, because the number of ethanol molecules in the diagram is greater than that of water, so ethanol is the solvent.
(b) Water, because equal masses correspond to equal volumes, making the mixture 50\% water by volume and therefore water acts as the solvent.
(c) Water, because it is present in the greater number of particles even though the masses were equal.
(d) Ethanol, because its larger molar mass means the equal masses contain more moles of ethanol, so ethanol is the solvent.