CHM1045 CH6 Terms: Composition of Substances and Solutions

Aqueous solution

Solution for which water is the solvent.

Avogadro's number

Experimentally determined value of the number of entities comprising 1 mole of substance, equal to 6.022*10^(23)mol^(-1).

Concentrated

Qualitative term for a solution containing solute at a relatively high concentration.

Concentration

Quantitative measure of the relative amounts of solute and solvent present in a solution.

Dilute

Qualitative term for a solution containing solute at a relatively low concentration.

Dilution

Process of adding solvent to a solution in order to lower the concentration of solutes.

Dissolved

Describes the process by which solute components are dispersed in a solvent.

Empirical formula mass

Sum of average atomic masses for all atoms represented in an empirical formula.

Formula mass

Sum of the average masses for all atoms represented in a chemical formula;for covalent compounds, this is also the molecular mass.

Mass percentage

Ratio of solute-to-solution mass expressed as a percentage.

Mass-volume percent

Ratio of solute mass to solution volume, expressed as a percentage.

Molar mass

Mass in grams of 1 mole of a substance.

Molarity (M)

Unit of concentration, defined as the number of moles of solute dissolved in 1 liter of solution.

Mole

Amount of substance containing the same number of atoms, molecules, ions, or other entities as the number of atoms in exactly 12 grams of carbon-12.

Parts per billion (ppb)

Ratio of solute-to-solution mass multiplied by 10^9.

Parts per million (ppm)

Ratio of solute-to-solution mass multiplied by 10^6.

Percent composition

Percentage by mass of the various elements in a compound.

Solute

Solution component present in a concentration less than that if the solvent.

Solvent

Solution component present in a concentration that is higher relative to other components.

Volume percentage

Ratio of solute-to-solution volume expressed as a percentage.