Topic 6 Flashcards
How is rate of reaction calculated?
Amount of reactant used or product formed
/
Time
Name 3 common ways of measuring rate of reaction
Loss in mass of reactants
Volume of gas produced
Time for a solution to become opaque
State 5 factors affecting the rate of a chemical reaction
Concentration of reactants Pressure of gases Surface area Temperature Catalysts
What is the collisions theory?
Chemical reactions can occur only when reacting particles collide with each other with sufficient energy (more than or equal to activation energy)
What is the effect of increasing temperature on the rate of reaction?
Temp increases, faster reaction
As T increases, kinetic energy increases, more collisions
However, no straight line relationship between rate and temp (not directly proportional)
What is the effect of increasing concentration on the rate of reaction?
Concentration increases, faster reaction
More reactions, more frequent collisons
What is the effect of increasing pressure of a gas on the rate of reaction?
Same as increasing concentration
Increases molecules in the same volume- increases rate
Volume and pressure are inversely proportional
What is the effect of increasing SA?
Increases frequency of collisions and increases rate of reaction.
What is a catalyst and how does it work?
Changes rate of reaction but isn’t used up
Increases rate by providing different pathway which has lower activation energy.
What is an enzyme?
Molecule that acts as a catalyst in a biological system
What is a reversible reaction?
Occurs when products of reaction can react backwards to produce original reactants
When is dynamic equilibrium reached?
In a closed system, when the forward and reverse reactions occur at the same rate and the concentrations of reactants and products remain constant
Describe Le Chatelier’s principle
If a system is at equilibrium and a change is made to any of the conditions, the system responds to counteract change and restore the equilibrium
