1. Energy in Chemical Reactions

2. Exothermic Reactions Heat (energy) is produced Heat (energy) is produced Feels Hot to the touch Feels Hot to the touch C 3 H 8 + O 2  CO 2 + H 2 O + Heat C 3 H 8 + O 2  CO 2 + H 2 O + Heat

3. Endothermic Reactions Heat (energy) is needed as a reactant Heat (energy) is needed as a reactant 6CO 2 + H 2 O + Heat  C 6 H 12 O 6 + 6O 2 6CO 2 + H 2 O + Heat  C 6 H 12 O 6 + 6O 2 Feels cold to the touch Feels cold to the touch

4. How Fast a Reaction happens Inhibitor- Slows down a chemical Reaction Inhibitor- Slows down a chemical Reaction –Is not used up in the reaction Ex. Food Preservative Catalyst- speeds up a reaction Catalyst- speeds up a reaction –Is not used up in the reaction Ex. Palladium

5. Unit 4 Test Topics Types of Bonds 1. Covalent – Formula and Names 1. Covalent – Formula and Names 2. Ionic 2. Ionic Counting Atoms Counting Atoms Formulas, Names and BIP’s Formulas, Names and BIP’s 3. Balancing Chemical Equations 4. Types of Reactions 5. Energy in Reactions