Mixtures

Mixtures A combination of two or more pure substances that are not chemically combined. substances held together by physical forces, not chemical No chemical change takes place Each item retains its properties in the mixture They can be separated physically Chem4kids.com

MIXTURES Components of a mixture do not have a definite ratio. Air is a mixture that is composed mostly of nitrogen and oxygen. It also contains carbon dioxide and water vapor. On some days there is more water vapor in the air than on others.

Separation Techniques For Mixtures Filtration Crystallization Distillation Chromatography Centrifuge

Distillation A liquid may be separated from a solution by distillation. The solution is heated until it boils. The vapor is cooled in the condenser, where it returns to liquid and is then collected in a container. The collected liquid is called the distillate.

Filtration A solid which has not dissolved in a liquid can be separated by filtration The solid remaining in the filter paper is called the residue. The liquid which has passed through the filter paper is called the filtrate

Crystallization A solid which has dissolved in a liquid (called a solution) can be separated by crystallization.

Crystallization The solution is warmed in an open container, allowing the solvent to evaporate, leaving a saturated solution. As the saturated solution is allowed to cool, the solid will come out of the solution, and crystals will start to grow. The crystals can then be collected and allowed to dry.

Thin layer Chromatography

Centrifuge