Solutions

Solutions• Solution- well-mixed mixture that

contains a solute and a solvent • Solvent- BIGGEST part of a solution

– Ex. water in lemonade– Solvent increases the boiling point

• Solute- SMALLEST part of a solution– Ex. lemon in lemonade– Solute decreases the boiling point

• A solution has the same properties throughout. The particles are too small to see.

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Colloid

• Colloid- mixture containing small, undissolved particles that do not settle out

• Colloids contain larger particles than solutions. The particles are still too small to be seen easily, but are large enough to scatter a light beam,– Ex. jello, milk, mayonnaise, shaving

cream, and whipped cream

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Supensions

• Suspension- mixture in which particles can be seen and easily separated by settling or filtration– Ex. pepper and water

• A suspension is different from a solution because a suspension does not have the same properties throughout.

• The particles in a suspension are larger than in a colloid or solution

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Unknown Solutions

• You have water with sugar and water with salt, but you do not know which is which.– Remember in science class, we do not taste

the solutions.– Sugar is not ionic while salt is.– Electricity can move through salt water not

sugar water.– So therefore to find out which one is salt, run

electricity through it and if the electricity flows, it’s salt water.

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Concentration• Dilute solution- mixture that only has a

little solute dissolved in solvent– Ex. watered down kool-aid

• Concentrated solution- has a lot of solute and a little solvent– Ex. REALLY strong coffee

• To measure concentration, you take the mass of the solute divide it by the mass of the solvent. The multiply it by 100.

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Solubility•Solubility- measure of how much

solute can dissolve in a solvent•Saturated solution- the most

solute that can dissolve has been added (no more can be added)

•Unsaturated solution- not all of the solute has been added

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Factors that affect solubilty

•The higher the pressure, the higher the solubility.

•The higher the temperature, the higher the solubility.

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Diffusion•Diffusion- movement of any molecule from an area of high concentration to a low concentration

•This is a form of passive transportation

•Passive transportation- Transportation of materials without using energy

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Osmosis•Osmosis- the movement of

water molecules from an area of high concentration to an area of low concentration.

•Osmosis is a form of passive transport

•This is ONLY done with water http://www.biologycorner.com/bio1/diffusion.html#

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Hypertonic Solutions•Hypertonic solutions-contain a

high concentration of a substance that is not water (e.g. the cell's cytoplasm).

•When a cell is placed in a hypertonic solution, the water moves out of the cell, causing the cell to shrivel.

http://www.tvdsb.on.ca/westmin/science/sbi3a1/Cells/Osmosis.htm

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Hypotonic Solution

•Hypotonic solutions-contain a high concentration of water

•When a cell is placed in a hypertonic solution, the water moves in the cell, causing the cell to swell and explode.

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Isotonic Solution

• Isotonic Solutions-contain the same concentration of water inside the membrane as outside the membrane

•When a cell is placed in an isotonic solution, the water diffuses into and out of the cell at the same rate. http://www.tvdsb.on.ca/westmin/science/sbi3a1/Cells/Osmosis.htm

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Active Transport•Active transport- movement of molecules from high concentrations to an area of low concentration and must have energy to do this

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Acids and Bases

Acid•Acid- any compound that

increases the number of hydronium ions when dissolved in water

•Always has a hydrogen ion or H –Ex. HCL

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Acid Properties•Sour tasting•Acids react with metals

(corrosive)•Turns yellow when added to

bromthymol blue•Turns blue litmus, red•Citrus fruits

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Base•Base- any compound that increases the number of hydroxide ions when dissolved in water

•Always contains an 0H group–Ex. NaOH

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Properties of Bases

•Bitter taste•slippery feel•In bromthymol blue, a base

changes to a dark blue•Turns red litmus, blue•Used in soaps and detergents

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Neutralization•Neutralization- when you add a base and an acid, it produces water and a salt

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pH•pH- value that is used to express the acidity or basicity

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On the pH scale• Acids are from 1-6• 7 is neutral• Bases are from 8-13• The lower the acid the stronger it is

and the higher the base the stronger it is

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