1. Reaction Rates

2. Chemical Reaction Rates
Chemical reactions can occur at different speeds
Some are fast (like explosions)
Some are slower
Yeast and CO2
Can we change the rates of reactions?

3. Reaction Rates
Chemical reaction speed can be affected by several factors:
Temperature
Surface area
Concentration

4. Temperature Most reactions proceed faster at higher temperatures. Why?
Particles are moving faster, so they collide more and have more of a chance to react.

5. Surface Area Surface area is the area (length x width) of an object
The smaller an object is, the more surface area it has compared to its volume.
If you put a whole potato in water to boil, how much of it is in contact with the water?
What if you cut it up? Would this speed up its cooking time? Why?

6. Concentration
The concentration of a substance refers to how much of it there is in a given volume.
Kind of like density!
Typically, higher concentrations of reactants react faster than lower concentrations.

7. Catalysts A catalyst is a substance that is used to speed up reactions
One specific type of catalyst is called an enzyme
Ex: digestive enzymes help your body chemically break down food.