Grade 7 Science Pure Substances and Mixtures Ms. Willis.
-
Upload
allison-lambert -
Category
Documents
-
view
257 -
download
3
Transcript of Grade 7 Science Pure Substances and Mixtures Ms. Willis.
Separating SolutionsGrade 7 Science
Pure Substances and MixturesMs. Willis
Learning Goals / Success CriteriaI can describe the processes used to separate
solutions into their components and identify some industry applications of these processes.
Vocabulary: evaporate, evaporation, distillation
Particles of SolutionsRecall that solutions are mixtures in which the particles of the different components are so completely mixed that the mixture appears to be a single substance.
E.g.: Salt water in the ocean…..
How can we separate Solutions?
1. Evaporation
2. Distillation
EvaporationDefinition: the process by which a sample
of matter changes from a liquid to a gas. The solid (or a more concentrated solution) is left behind.
Evaporation is often used to remove the liquid from a solution made of a liquid and a solid.
EvaporationMaple syrup is made by
boiling the sap which evaporates the water and leaves the concentrated solution (syrup) or sugar behind.
Releasing water vapor into the air is not harmful, however, burning fossil fuels to make the heat can be polluting.
DistillationDefinition: the process of separating liquids
in a solution by heating the solution, trapping and cooling the gas, and collecting the resulting pure liquid.
Short video to illustrate:https://
www.youtube.com/watch?v=xxNfJLMNS4E
If you had a liquid solution with more than two liquid components, you could repeat the distillation process to separate all the liquid parts of the solution and use a different collecting flask for each component.
Distillation
DistillationPicture of a seawater distillation plant:
(Seawater must go through several stages to become drinking water.)
Distillation
New technologies are going beyond simple distillation for “desalinating” water:
A closer look at desalinating seawater:https://
www.youtube.com/watch?v=aysj7696b0A