 Section 1: Working With Solutions  There are two types of mixtures:  1) Solutions are well mixed mixtures. You can’t separate them with filters, BUT you can boil the water away and it will leave it behind. Examples: Salt water, cool aid etc.  2) Suspensions are mixtures that contain particles that can be seen and separated by a filter. Examples: Muddy water, paint, flour and water, blood

 Solutions are made of two parts 1) Solvents: That which dissolves a substance. 2) Solutes: A substance that is dissolved in a solvent and is present in a smaller amount.

 Why is water called the “universal solvent?”  It dissolves a lot of substances…not all, but a whole bunch! Thirsty?

 Gasoline: A solution of different fuels. Several hydrocarbons and ethanol (Biofuel.)  Brass: A solution of zinc and copper  Air: A solution of Nitrogen, Oxygen and other gases.

 Two different concentrations: 1) Dilute Solutions: A little solute is dissolved in a solvent. 2) Concentrated Solution: Solutions with a lot of solute dissolved in a solvent.

 A measure of how well a solute can dissolve in a solvent at a given temperature.  A saturated solution is holding the maximum amount of solute it can. Add more and it will settle to the bottom of the solvent.  An unsaturated solution can hold more solute to bring it up to saturation.  Sponge Example!

 You can dissolve more solutes (like Cool aid) in warm water than you can in cold. It dissolves faster too!  Example: Mr.Lynch’s Coolata!

 Data:  Temp( o C) Solubility (g/100g of H2O)  0 13     

 1) Determine what goes on the x and y axis. Do this by asking yourself, does solubility affect temperature or does temperature affect solubility. The one that affects the other is the X axis variable. (A.K.A. independent variable.) The Y variable is the other. (A.K.A. dependent variable.)  2) Choose number scales that cover all of your values. Use a continuous increment.

 Continuous increment means going with the same increase each time. Example: 0,2,4,6,8 (2 is the increment) or 0,3,6,9,12 (3 is the increment)  Graphs aren’t worth the paper they’re printed on without continuous increments!

Y X HUH?

 Data:  Temp( o C) Solubility (g/100g of H2O)  0 13     

 Lower Freezing Points: Adding solute to solvents will lower the freezing temperatures of the solution Example: Water will freeze at a lower temperature when the solute salt is dissolved in it. That’s why we use it on roads in the winter time! The ice will form at lower temperatures.

 Higher Boiling Points: The addition of a solute to a solvent will increase the boiling temperature of the solution. Example: We add salt to boiling water to make it boil at a higher temperature. It cooks the food faster!

 Acids: -Produce H+ ions in water -Taste sour (Don’t try this at home!) -React with metals and carbonates -Turn blue litmus paper red Examples:

 Bases:  -Produce OH- ions in water  -Taste Bitter (DON’T)  -Feel slippery  -Turns red litmus paper blue  Examples:

 Strength of acids and bases means how well they break up into ions in water. Ex: If you put an acid in water and it breaks up into a lot of H+ ions it’s a strong acid. A few H+ ions it’s a weak acid. Hydrochloric Acid is strong Acetic Acid is weak

 If you put a base in water and it breaks up into a lot of OH- ions, it’s strong. A little, it’s weak.  Ex: Sodium Hydroxide is a strong base and Ammonia is a weak base.

 A strong acid or base is still strong even if you dilute it with a lot of water. They still readily break up into ions but the damaging effects of the acids and bases will be reduced when they’re dilute.  The most dangerous acids and bases are concentrated strong acids and bases.

 -Helps us determine whether a solution is an acid or a base by measuring the concentration of H+ ions in solution  It’s a scale from 0-14  0-6 are acids. 0=strong, 6=weak  7 is a neutral solution. Neither acid or base.  8-14 are bases. 8 is a weak base, 14 is a strong base.

 The process of mixing an acid and a base in exact quantities to produce a neutral solution (pH of 7) made of water and salt.  If you don’t mix exact quantities the solution will still be either acidic or basic depending on which there was more of at the start.

 Acid + Base = salt and water  Hydrochloric Acid + Lye  Salt + Water  HCl + NaOH  NaCl + H 2 O