Separating mixtures is when you take all the elements in a mixture apart. There are many methods we can use to separate the elements in a mixture. For example if you have clumps of dirt in a glass of water you can put it through a filter to get some of the dirt out. Another method is evaporation. This is when a liquid changes to a gas. So you could put you dirty water over a very hot flame and over time it will evaporate and turn to a gas.