1. Acids, Bases , & Solutions

2. Solutions Solution-uniform mixture that contains a solvent & solute
Solvent-the part of the solution that is present in the largest amount
Solute-the part of the solution that is present in the smaller amount and is dissolved…
Water is the universal solvent, but solvents and solutes may be solids, liquids, or gases
Solutions have the same properties throughout

3. Colloids
a mixture that contains small undissolved particles, particles are too small to be seen, but large enough to scatter light

4. Suspension Does not have the same properties through out
Contains visible particles

5. Effects of Solute & Solvents
Solutes lower the freezing point & raise the boiling point of a solvent

6. Particles in Solution
When a solution forms, particles of the solvent surround and separate the particles of the solute. Ionic and molecular compounds in solution Ionic – positive and negative ions are attracted to the polar water molecules. These types of compounds in water will conduct electricity. Molecular – breaks up into individual neutral molecules (sugar)

7. Common solutions Solute Solvent Solution Gas
Air (oxygen and other gases in nitrogen)
Liquid
Soda water (carbon dioxide in water)
Antifreeze (ethylene glycol in water)
Solid
Dental filling (silver in mercury)
Ocean water (sodium chloride in water)
Stainless steel (chromium, nickel, and carbon in iron)

8. Concentration Concentrated solution-lots of solute, little solvent
Ex. Frozen juice
Dilute solution-little solute, lots of solvent
Ex. Frozen juice + water
Measuring concentration-compare amount of solute to solvent
Ex. 5 grams per 100mL

9. Solubility
How much solute can dissolve in a solvent at a given temperature
Unsaturated-can hold more solute
Saturated-can NOT hold more solute
Supersaturated-too much solute, some is undissolved at the bottom of the container

10. Factors affecting solubility
Pressure
Increasing the pressure increases the solubility and vise-versa
Type of solvent
Some solutes & solvents are incompatible
Ex. Oil and vinegar
The solvent affects the solubility of a substance
Ex. Oil-based paint & water

11. Temperature Increasing the temp. of a solid increases the solubility
Increasing temperature of a gas decreases the solubility

12. Acids and Bases Chemicals may be classified as acids or bases.
Things that are neither acids nor bases are neutral.
pH measures the acidicity or basidity of a solution

13. Acids Taste sour Turns blue litmus paper red
Reacts with metals/carbonates
Contains hydrogen ions H+
Examples:
Lemon juice
Vinegar
Car battery acid (dangerous!)

14. Acids and Bases
Some of our favorite foods make our tongue curl up because they are SOUR.

15. Bases Taste bitter Feel Slippery Turns red litmus paper blue
Contains hydroxide ions OH-
Turns Phenolphthalein pink
Examples:
Milk
Baking soda
Soap
Drain cleaner (dangerous!)

16. Bitter!
Some foods have a “bite” of their own because they’re somewhat bitter.

17. pH
A special name given to the acid or base characteristic is called: pH

18. How Do We Measure pH?
We measure pH by using special strips of paper called pH paper

19. How Does It Work?
The paper is treated with chemicals that change color to show the pH.
When the paper touches the substance being tested, it turns a specific color to tell if the substance is an acid or a base.

20. The pH Scale pH scale ranges from 0 -14
pH 7 is neutral; neither acid nor base
Pure water is pH 7
Low pH = acid
High pH = base
The closer to the ends of the scale, the stronger the solution

21. 0--------------7---------------14
Acid
Any substance which has a pH value less than 7 is considered an acid
Acid Neutral Base

22. 0--------------7---------------14
Base
Any substance which has a pH value greater than 7 is a base
Acid Neutral Base

23. pH 7 A pH of 7 is called neutral—neither acid nor base.
Acid Neutral Base

24. The pH Scale

25. The pH Scale Each pH unit is 10 times as large as the previous one
A change of 2 pH units means 100 times more basic or acidic
x10
x100

26. Acid-Base Reactions
Neutralization-a reaction in which an acid reacts with a base to produce salt and water
HCl + NaOH= H2O + NaCl