1. Chemical Reactions

2. What is a chemical reaction? A chemical reaction is the process by which one or more substances undergo change to produce one or more different substances.

3. 5 signs a chemical reaction has taken place 1.Formation of gases or solids 2.Energy change (heat or electricity) 3.Color change 4.Odor change 5.Not easily reversed

4. Chemical Formulas A chemical formula is an abbreviation for a chemical compound using chemical symbols and numbers. The subscript number tells how many atoms of the element are present in the compound Example: CO 2 = Carbon Dioxide –Di = 2 –1 Carbon atom and 2 oxygen atoms

5. Chemical Equations Chemical equations use chemical symbols to show the compound that is a result from a chemical reaction Example: C + O 2 CO 2 –Carbon + 2 Oxygen = Carbon Dioxide Example: Na + Cl NaCl –Sodium + Chlorine = Sodium Chloride

6. Parts of a chemical equation The reactants in a chemical reaction are the elements that combine to form a new substance The products are the new compounds

7. The total mass of the reactants must equal the total mass of the products Equations must balance on both sides of the equation Rules for chemical equations

8. Chemical Compounds Ionic Covalent Acids Bases Salts

9. Covalent Compounds Result of a chemical reaction between nonmetals DO NOT conduct electricity Have low melting points

10. Ionic Compounds A chemical reaction formed between a metal and a nonmetal Conduct electricity Have high melting points Brittle – ions shift when hit, this causes them to break apart

11. Acids A compound that increases the number of hydrogen ions (H + ) when dissolved in water Acids react with metals producing hydrogen gas Corrosive Conduct electricity Taste sour Found in batteries, your stomach, soft drinks

12. Bases Any compound that produces hydroxide ions (OH - ) when dissolved in water Feels slippery Tastes bitter Conduct electricity Examples: soap, oven cleaners, drain uncloggers, other cleaning products, antacids

14. An ionic compound formed from the POSITIVE ion of a BASE and the NEGATIVE ion of an ACID Example: Baking Soda – sodium bicarbonate –NaHCO 3 Salts