Purity + Formulations

• A pure substance is something that only contains one compound or element throughout, not mixed with anything else.
• A chemically pure substance will melt and boil at a specific temperature. You can test the purity of a sample by measuring it's melting/boiling point, and comparing it with the melting/boiling point of the pure substance.
• Impurities in a sample will lower the melting point, and increase the melting range. Impurities will also increase the boiling point, and may result in the sample boiling at a range of temperatures.
• Formulations are useful mixtures with a precise purpose, that are made by following a 'formula' (a recipe). Each component is present in a measured quantity, and contributes to the properties so that it meets it's required function.
• Paints are formulations of pigment, solvent, binder and additives.
• Formulations are important in the pharmacuetical industry. For example, by altering the formulation of a pill, chemists can make sure it delivers the drug to the correct part of the body - at the right concentration, that it's consumable and has a long enough shelf life.
• Formulations can be found in everyday life - such as cleaning products, fuels and cosmetics.