Rates Of Reactions (chpt. 16) Flashcards
Rate of reaction
The change in concentration of any one reactant or product per unit of time
Instantaneous rate of reaction
The rate of reaction at any one particular time during the reaction
Catalyst
A substance that alters the rate of a chemical reaction but is not consumed in the reaction
Enzyme
An enzymes is a a substance that is produced by a living cell and acts as a biological catalyst
Homogeneous catalysis
Catalysis in which both the reactants and the catalyst are in the same phase, i.e. there is no boundary between the reactants and the catalyst
Heterogenous catalysis
Both the reactants and the catalyst are in different phases
E.g. Oxidation of methane using a platinum catalyst
Autocatalysis
One of the products of the reaction acts as a catalyst for the reaction
↳ starts slowly but speeds up as the catalyst product forms
Catalytic converter
A device in the exhaust system of a motor vehicle which contains catalysts to convert pollutants in the exhaust gases to less harmful substances
Catalyst poison
A substance that makes a catalyst inactive
Effective collision
One that results in the formation of products
Activation energy
The minimum energy that colliding particles must have for a reaction to occur
Explain why increasing temperature has a significant effect on the rate of reaction
More effective collisions
State and explain three factors that have an effect on the rate of a chemical reaction
Concentration → more particles therefore more collisions
Particle size → greater surface area means more particles exposed for collisions
Nature of the reactants → ionic fast, covalent slow
Presence of a catalyst → lowers the activation energy
Give the name and symbol of one metallic element used as a catalyst in the catalytic converter of a car
Platinum Pt
Palladium Pd
Rhodium Rh
How can a catalyst lower the activation energy of a reaction
Provides alternative pathway / mechanism for the reaction
