Quantitative Analysis

molarity

moles of solute per liter of solution

molality

moles of solute per kilogram of solvent

formal concentration

formula units per liter of solution

percent composition

ratio of solute to total mixture/solution multiplied by 100, expressed as weight percent, volume percent, or weight-to-volume; needed when concentration is given or requested as a percentage by weight/volume

parts per million

concentration units for trace amounts representing mass ration multiplied by 10^6 or 10^9 respectively; needed when measuring extremely small concentrations

limiting reagent

the reactant in a chemical process that is consumed first, halting the reaction; needed when given specific starting amounts of two or more reactants in a chemical process

weighing by difference

a method to accurately measure mass by taring/weighing a filled container, transferring sample, and reweighing to subtract moisture absorption effects

relative uncertainty

the absolute uncertainty divided by the total magnitude of the measured quantity, often multiplied by 100 to show percentage; needed to evaluate precision or compare error levels across different measurement volumes or tools

class A glassware

high-accuracy laboratory glassware manufactured to meet precise volumetric tolerance standards

dilution

needed when preparing a lower-concentration solution using a stock solutionsto

stock solutionuob

concentrated solution that you dilute to create working solutions as needed

buoyancy correction

needed for high-accuracy mass measurements where the object’s density differs significantly from the balance standard weights