Bell Ringer 4-29-09
1. When we balance equations, we only change _________, not
2. T/F: Balanced chemical equations should have the same number of
atoms on each side of the arrow.
3. Chemical equations are just abbreviations using chemical
_______ and numbers.
4. In 2C6H2O5, how many atoms of Hydrogen are there?
#1- Identify the steps of the scientific method
#4 State the law of conservation of matter
(Balancing Chemical Equations)
Chapter 6 Section 3
Controlling Chemical Reactions
To start a chemical reaction you need
Activation energy is the minimum amount
of energy needed to start a chemical
P. 206 in textbook
Chemical reactions do not all occur at the same
Explosions really fast
Rusting much slower
Rate of Reaction
Rate of reaction tells us how fast a reaction occurs.
To find the rate of reaction, you can measure either how quickly the
reactant is disappearing or how quickly the product is appearing.
Ex. If it takes 1 minute for 2 inches of the candle to burn, how many
minutes will it take for 6 inches of the candle to burn.
What affects the rate of reaction?
Concentration- the amount of substance present.
Surface area – how big or small the area is or how
much is being exposed
Temperature – hot or cold
Inhibitor – slows down a chemical reaction. (ex:
Catalyst – speeds up a chemical reaction. (ex:
Ex. Enzymes – breaks down food. Make it possible
for your body to function properly.