Standard solution in the context of Accuracy and precision

The standard state of a material (pure substance, mixture or solution) is a reference point used to calculate its properties under different conditions. A degree sign (°) or a superscript ⦵ symbol () is used to designate a thermodynamic quantity in the standard state, such as change in enthalpy (ΔH°), change in entropy (ΔS°), or change in Gibbs free energy (ΔG°). The degree symbol has become widespread, although the Plimsoll symbol is recommended in standards; see discussion about typesetting below.

In principle, the choice of standard state is arbitrary, although the International Union of Pure and Applied Chemistry (IUPAC) recommends a conventional set of standard states for general use. The standard state should not be confused with standard temperature and pressure (STP) for gases, nor with the standard solutions used in analytical chemistry. STP is commonly used for calculations involving gases that approximate an ideal gas, whereas standard state conditions are used for thermodynamic calculations.

A volumetric flask (measuring flask or graduated flask) is a piece of laboratory apparatus, a type of laboratory flask, calibrated to contain a precise volume at a certain temperature. Volumetric flasks are used for precise dilutions and preparation of standard solutions. These flasks are usually pear-shaped, with a flat bottom, and made of glass or plastic. The flask's mouth is either furnished with a plastic snap/screw cap or fitted with a joint to accommodate a PTFE or glass stopper. The neck of volumetric flasks is elongated and narrow with an etched ring graduation marking. The marking indicates the volume of liquid contained when filled up to that point. The marking is typically calibrated "to contain" (marked "TC" or "IN") at 20 °C and indicated correspondingly on a label. The flask's label also indicates the nominal volume, tolerance, precision class, relevant manufacturing standard and the manufacturer's logo. Volumetric flasks are of various sizes, containing from a fraction of a milliliter to hundreds of liters of liquid.

Titration (also known as titrimetry and volumetric analysis) is a common laboratory method of quantitative chemical analysis to determine the concentration of an identified analyte (a substance to be analyzed). A reagent, termed the titrant or titrator, is prepared as a standard solution of known concentration and volume. The titrant reacts with a solution of analyte (which may also be termed the titrand) to determine the analyte's concentration. The volume of titrant that reacted with the analyte is termed the titration volume.