# C8 - Rates and Equilibrium

• Created by: 15j.price
• Created on: 14-04-19 11:52
• C8 - Rates and Equilibrium
• 8.1: Rates of Reactions
• rate of reaction = amount of reactant used / time(s)
• rate of reaction = amount of reactant used / time(s)
• same gas escapes at the beginning
• mass loss, only gas esapes
• 8.8: Dynamic Equilibrium
• 2. rate of forward reaction slows down, backward reaction speeds up
• 3. rate of forward and backward reaction is equal
• END
• Le Chalelier's Principle
• whenever a change in condition is made the position of equilibrium moves to cancel out the change
• 1. forward reaction(fast), no backward reaction
• START
• A+B     C+D
• ADDED C: Equilibrium shifts to the left to remove excess C
• LOSE D: Equilibrium shifts to the right to replace D
• ADDED A: Equilibrium shifts to the right to remove excess A
• when a reaction has reached equilibrium the forward reaction and the backward reaction are occurring at the same time
• Equilibrium
• 8.3: Effect on Temperature
• Increasing the temperature increase collisions which means particles have more kinetic energy, more have the activation energy which results in more successful collisions, this means faster rate
• higher temperature = higher collisions
• 8.7: Energy and Reversible Reactions
• A+B --->C+D
• 8.2: collision theory and surface area
• COLLISION THEORY: Reactions only take place when the particles (atoms, ions or molecules) of reactants come together. The reacting particles do not only have to bump into each other, but also need to collide with enough energy to cause a reaction to take place
• INCREASE THE RATE OF REACTION: catalyst, surface area, temperature, concentration
• the surface area to volume ratio will be larger in granulate sugar. This means there will be a higher frequency of collisions
• smaller particles = larger surface area
• more collisions = faster reaction rate
• 8.6: Reversible Reactions
• not reversible, strong acid
• reversible, weak acid
• INDICATOR: Methyl Orange, ACID: red, ALKALI: orange / yellow
• INDICATOR: Phenolphthalein, ACID: clear, ALKALI: pink
• INDICATOR: Litmus, ACID: red, ALKALI: blue
• 8.4: Effect on Concentration and Pressure
• CONCENTRATION: Increasing concentration increases the rate of reaction. More particles in the same volume meaning more collisions
• PRESSURE: Increasing the pressure increases the rate of reaction. Particles are closer together therefore there are more collisions
• 8.9: Altering Conditions
• Increasing temperature favors the endothermic reaction. Decreasing favors the exothermic reaction
• Increasing pressure moves the positions of equilibrium to the side with the fewest number of gas molecules
• 8.5: Effect of Catalysts
• reduce energy costs
• The reaction profile of an uncatalysed and a catalysed exothermic reaction. The catalyst lowers the activation energy of the reaction