solutions solutes, solvents & solutions. mixtures you should be able to recall what a mixture...
DESCRIPTION
Solutions Solutions are mixtures in which soluble particles are completely dissolved in a liquid or a gas. Made up of a; Solute Solvent We will use coffee as an example of a solution The substance that dissolves is called the solute In this example the coffee granules The substance that does the dissolving is called the solvent In this example the hot waterTRANSCRIPT
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SolutionsSolutes, Solvents & Solutions
Mixtures
You should be able to recall what a mixture is. Two or more substances that are mixed together but not
chemically bonded to each other. Easiest example is saltwater or seawater
The proportion in a mixture is not fixed If you have lots of salt or very little salt the mixture is still
considered saltwater
Solutions
Solutions are mixtures in which soluble particles are completely dissolved in a liquid or a gas. Made up of a;
Solute Solvent
We will use coffee as an example of a solution The substance that dissolves is called the solute
In this example the coffee granules The substance that does the dissolving is called the solvent
In this example the hot water
Solutions
Black Tea
Mi-Wadi
Seawater
Wine
Fizzy Drinks
Substance Solvent Solute
Water
Water
Water
Water
Water
Tea
Flavours and Sugar
Salt
Flavours/Sugar/Carbon Dioxide
Grape Juice and AlcoholWater is called the universal solvent, as it can dissolve many substances
Solvents
Water is described as the universal solvent However there are other solvents
Ethanol Acetone (Nail polish remover) Toluene (Paint thinner) Chloroform
Solvents can be dangerous Think of the common hazard symbols Toxic Flammable Irritant Can cause significant health issues if abused
Solutions
Solutions do not have to be made from a solid and a liquid.
Solutions can also be made by dissolving a gas into a solvent. Oxygen is dissolved in water allowing marine life to
breathe Solutions can also be made from a liquid mixing with
another liquid Alcohol is dissolved in wine, beer, etc.
Dilute vs Concentrated
We can change the strength of the solution, i.e. its taste, colour, smell , etc… by changing the amount of solute used.
A dilute solution has a small amount of solute in a large volume of solvent.
A concentrated solution has a large amount of solute in a small volume of solvent
Soluble vs Insoluble
If a substance is soluble it will dissolve in a liquid and if it is insoluble it will not dissolve Calcium carbonate is not soluble in water because the
calcium carbonate and water particles are not able to mix. Copper sulfate is soluble in water because the copper sulfate
and water particles are able to interact and mix together.
Calcium Carbonate Copper Sulphate
water
Immiscible Liquids
Liquids that do not mix together are called immiscible liquids
Examples are Oil and water Toluene and water Gasoline and water
Liquids that do mix together are called miscible
oilwater
Suspensions
Suspensions are mixtures in which insoluble particles are suspended in a liquid or gas.
Examples of suspensions are; Milk Oil shaken in water Dust in air Sandy water
Insoluble substance
+ Solvent = Suspension
Sand + Water = Sandy water suspension
Conservation of Mass
If 10g of salt is added to 50g of pure water than the solution should have a mass of 60g.
+ =
50 g 10 g+ = 60 g
Solutions
The amount of solute that can dissolve in a solvent at a given temperature is called its solubility
The amount of a solute that can dissolve in a solvent can be increased by increasing a solvent’s temperature This is generally true A gas’ solubility decreases as the solvent temperature increases
Problem with the oceans warming due to climate change.
A solute will not dissolve in a solvent indefinitely. Eventually it reaches a limit where no more will dissolve
At this point the solution is described as saturated
Solubility Curve
Supersaturated solutions are very saturated indeed.
The solute will stay in solution until a ‘seed’ crystal is added, and then it will crystallise out of the solution very quickly.When it does this, it gives out heat energy. Supersaturated solutions are therefore used in heat packs.