Mixtures and Separating Techniques Flashcards
What is a mixture?
Mixtures include two or more elements/compounds not chemically combined. They can be homogenous (solutions/uniform), or heterogenous (non-uniform). Mixtures can be separated by physical or chemical means, and its properties are similar to its components.
Examples of mixtures
Solid/solid: coffee power + sugar
Liquid/liquid: cordial + water
Gas/gas: air + perfume
Solid/liquid: sol + gel, coffee powder + sugar + water
Solid/gas: styrofoam
Liquid/gas: water + carbon dioxide
What is a solution? What is a solute and solvent?
A solution is when one substance dissolves into another.
A solute is the substance that dissolves and the solvent is the substance it dissolves into.
What is the most common solvent?
Water.
What is a suspension?
A suspension is a mixture in which the particles do not dissolve even though they may look like it. When suspensions are left alone, one lot of the particles will settle to the bottom (sediment).
What is a sediment?
Particles that settle to the bottom of a mixture.
What is a colloid?
A mixture in which the particles don’t dissolve but they also don’t settle out quickly - more opaque.
What is filtration?
Solid particles being filtered out of liquids or gases using filter paper and a funnel - lets the liquid pass through but stops the solid particles.
Filtration is based off of size and solubility e.g. sand and water.
What is evaporation?
Separating solids that have been dissolved into a liquid using heat (turns the liquid into a gas, leaving the solid).
Evaporation is based off of boiling point e.g. salt and water.
What is distillation?
Separating liquids from dissolved solids - the liquid is heated into a gas (vapour) which is then caught and condensed back into a liquid, saving both the liquid and solid.
Distillation is based off of boiling point e.g. salt and water.
What is chromatography?
Using how fast the liquids and gases move to separate them (layers). It is used more to identify and analyse substances.
Chromatography is based on density and speed e.g. testing water samples for pollutant.
What is magnetic separation?
Using magnets to separate magnetic materials from non-magnetic materials.
Magnetic separation is based off of magnetic attraction e.g. iron fillings from sand.
What is centrifuge?
Liquids separating from solids/non-miscible mixtures by placing the mixture into a tube and spinning it a very high speeds. This causes a part of the mixture to settle at the bottom and then form layers.
Centrifuge is based off of density e.g. fat from milk.
What does immiscible (non-miscible) mean?
Liquids that are not able to combine and create a homogenous mixture.
What does homogenous mean?
A mixture that has equal proportions all throughout.
