CHARACTERISTICS OF THE BOILING POINT FOR PURE SUBSTANCES:
The boiling point of a substance is the temperature at which the vapor pressure of a liquid equals the pressure surrounding the liquid and the liquid changes into a vapor. ... For example, water boils at 100 °C (212 °F) at sea level, but at 93.4 °C (200.1 °F) at 1,905 metres (6,250 ft) altitude.
WHAT THEY HAVE IN COMMON:
Mixtures and pure substances are alike because mixtures are made up of two or more pure substances. This means that where pure substances have a single set of properties, mixtures may have two or more sets of the same properties, based on the pure substances that make up the mixture.
CHARACTERISTICS OF THE BOILING POINT FOR MIXTURES:
Mixtures also tend to melt at temperatures below the melting points of the pure solids. When a liquid is heated, it eventually reaches a temperature at which the vapor pressure is large enough that bubbles form inside the body of the liquid. This temperature is called the boiling point.