Chemical Chemical ReactionsReactions

88thth 5.2 Rates of Chemical 5.2 Rates of Chemical ReactionsReactions

RatesRates

It takes energy to break bonds.It takes energy to break bonds. Energy required to start a Energy required to start a

chemical reaction is called chemical reaction is called Activation Energy.Activation Energy.

Reaction Rate – the speed of a Reaction Rate – the speed of a reactionreaction

Factors that affect reaction rateFactors that affect reaction rate

Activation Energy

RatesRates

Temperature – increase temp. = Temperature – increase temp. = increase rateincrease rate

Concentration – larger conc. = Concentration – larger conc. = increase rateincrease rate

Particle Size – increase part. Size Particle Size – increase part. Size = decrease rate= decrease rate

Inhibitors – slows down the speed Inhibitors – slows down the speed of a reactionof a reaction

RatesRates

Catalysts – speeds up the speed of Catalysts – speeds up the speed of a reactiona reaction

Catalysts don’t affect the outcome Catalysts don’t affect the outcome of the reaction or the of the reaction or the temperature of the overall temperature of the overall reaction.reaction.

CC22HH44 + H + H22 + platinum → C + platinum → C22HH66

Enzymes – large protein Enzymes – large protein molecules that act as catalystsmolecules that act as catalysts