Mixture Separation

• A solution is a mixture, but a mixture isn't always a solution.
• Mixtures can be separated using knowledge of solids, liquids, and gases

Separating Mixtures

• Mixtures can be separated into their constituents using physical methods, without chemical reactions.
• Separation techniques are physical methods, and choice depends on constituent properties.
• Examples of separating mixtures: sieving, decanting, filtering, evaporating, distillation, chromatography

Sieving

• Used for separating solids by particle size.
• A sieve separates larger solids from smaller ones using a meshed bottom.
• In the sieving process, a mixture (e.g., sand and gravel) is poured through a sieve.
• Gravel particles, being larger than the sieve holes, remain on the sieve while smaller sand particles pass through.

Filtration

• Used for separating materials, specifically small, insoluble solids, from liquids using a filter.
• Fine sand and water is an example of something filtration can separate.
• A filter is a semi-permeable material, allowing some substances to pass through but not others.
• In the process, a mixture is poured into a filter funnel lined with filter paper.
• The filter paper allows water but not sand to pass through, separating the water from the sand.
• The sand left on the filter paper is called residue.
• The liquid that drips is known as the filtrate, and it is collected in a beaker below the funnel.

Distillation

• Distillation purifies a liquid using temperature changes, converting it to vapor and then condensing it back to liquid.
• Distillation begins by heating a liquid to its boiling point, causing it to evaporate into a vapor.
• The vapor is then cooled, often by passing it through pipes or tubes at a lower temperature.
• The cooled vapor condenses, forming a distillate - a purified form of the original liquid.
• As the liquid evaporates, impurities are left behind, preventing them from appearing in the distillate.

Sedimentation

• Sedimentation, or clarification, involves letting suspended material settle by gravity.
• Suspended material includes items such as clay or silts, originally present in the source water.
• A mixture (possibly from a precipitation reaction) stands, allowing gravity to pull solids to the container's bottom.
• Gravity's effectiveness relies on the solid being denser than the liquid.
• Clear water from mud may be obtained this way, simply by allowing time for the solids to separate.
• Separation occurs after gravity pulls denser particles bottom, forming a layer of sediment.
• The clearer liquid at the top is then separated for further use.

Decantation

• Decantation separates mixtures of immiscible liquids or liquid and solid mixtures like suspensions.
• Oil and vinegar mixtures exemplify decantation.
• After settling, the oil will float on top of the water, allowing the two components to be separated.