1. Warm Up: 11/29/16

2. What is a chemical reaction?
A chemical reaction is a process in which a substance changes into an entirely different substance
Two main components of a chemical reaction are a:
Reactant
Product

3. Reactants vs Products Reactants – the starting materials in a reaction
(the things we mix together)
Products – are the materials produced from the reaction
(What we get after the reaction has taken place)

4. The arrow always points to the products
Reactants Products
The arrow always points to the products

5. 2H2 + O2 2H2O C + O2 CO2

6. Chemical Reaction Two main types of bonds
During a chemical reaction the reactants and the products have the same atoms. They just rearrange partners and switch partners.
Chemical bonds break in the reactants and new chemical bonds form in the products.
Two main types of bonds
Covalent – share electrons (Married)
Ionic – share charges (Dating)

7. How A Reaction Works

8. CH4 + H2O CO + 3H2 CO + H2O CO2 + H2
The arrow always points to the products

9. Energy in a Reaction
Endothermic Reaction – a chemical reaction that absorbs heat energy from its environment (Temperature Drops)
Exothermic Reaction – a chemical reaction that releases heat energy to its environment (Temperature Increases)

10. Common Significant Reactions
Combustion Reaction (Hydrocarbons) – Fuel or gas reacting with oxygen
Reactions only made up of carbon (C) and hydrogen (H)
CH4 + H2O CO + 3H2

11. Photosynthesis – the process of turning sunlight into food
Light energy to chemical energy
6CO + 6H20 C6H12O6 + 6O2
Respiration (Cellular Respiration) – the process of turning sugar and oxygen into carbon dioxide and water.
C6H12O6 + 6O2 6CO + 6H20

12. Why must both the reactant and the products have the same number and kinds of atoms?
It’s the law – the law of conservation of mass
Matter cannot be created or destroyed
In every chemical reaction, the mass of the matter in the products must equal the mass of the reactants.

13. Law of Conservation of Mass
Matter can’t be created or destroyed
The mass of the products must equal the mass of the reactants.
Same number/kinds of elements on both sides

15. Reactions Rates Think of rate as how fast or slow the reaction happens
What factors influence how fast a reaction happens?

16. 4 Factors that Influence Reaction Rates
Temperature or reactants
Concentration of reactants
Surface area of reactants
Presence of a catalyst

17. Temperature of Reactants
Higher temperatures react faster than cooler temperatures

18. Concentration of Reactants
Concentration is the number of particles in a given volume
The higher the concentration the faster the reaction
The lower the concentration the slower the reaction

19. Surface Area of Reactants
The more surface (matter) area exposed the faster it reacts

20. Presence of a Catalyst Something we add to a reaction to speed it up.
IS NOT a reactant and is not consumed in the reaction.
It DOES NOT take part or participate in the reaction.
Takes less energy to make the product