1. Types of Formulas 1)Simple Formula: shows the number and kinds of atoms in a compound. EX: H 2 O (2 hydrogen, 1 oxygen) CO 2 (1 carbon, 2 oxygen)

2. 2) Structural Formula: shows number and kinds of atoms,as well as the arrangement of atoms in the compound. EX: Methane (CH 4 ) H H C H H

3. Solutions A solution consists of one substance dissolved within another substance. Ex: Salt water, soda The substance in greater quantity is called the solvent. The substance in lesser quantity is called the solute.

4. There are three types of solutions: Solutions by definition are homogeneous, meaning they are uniform throughout. 1)A solid in a liquid, as in Kool-Aid or salt water. 2) A liquid in a liquid, as in alcoholic drinks or milk in coffee. 3) A gas in a liquid, as in seltzer water or carbonated drinks.

5. EX: Whiskey that is 160 “proof” is 80% alcohol, 20% water. Solvent: Alcohol Solute: Water EX: Whiskey that is 80 “Proof” is 40% alcohol, 60% water. Solvent: Solute: Water Alcohol

6. Ionic compounds separate into individual ions in solution, covalent compounds dissolve into individual molecules in solution. Ex: NaCl separates into Na+ and Cl- ions in a solution of salt water. Glucose (C 6 H 12 O 6 ), because it is a covalent compound, separates into individual glucose molecules.

7. Substances which contribute H+ ions into solution are called acids. Substances which contribute OH- ions into solution are called bases. Acids and Bases

8. EX: Hydrogen Chloride: In solution, breaks down into H+ and Cl- ions. HCl H+ + Cl- Because it contributes H+ ions, HCL is an acid

9. Ex: Sodium Hydroxide: -Contributes an OH- ion to solution NaOH Na+ + OH- Because NaOH contributes an OH- ion to solution,it is a base.

10. Pure water is termed NEUTRAL, because it contributes both H+ and OH- ions evenly to a solution. H 2 0 H + + OH- Water molecules are constantly going back and forth between whole molecules and charged ions.

11. Every jump of 1 on the scale represents a 10 X increase or decrease in acidity. pH Scale (1 – 14) Measures the relative acidity of substances. A pH of 7 is considered neutral

12. Some Common Items and their pH

13. A pH of 5 is 10 times less acidic than a pH of 4. Ex: a pH of 3 is 10 times more acidic than a pH of 4.