C8 Flashcards
How can you work out the rate of reaction?
By finding how quickly the reactants are used up as they make products or by the products being made.
How can you measure the decreasing mass of a reaction mixture?
You can measure the rate at which the mass of a reaction changes if the reaction gives a gas. You put a conical flask on a scale and add hydrochloric acid and marble chips, adding a cotton bung to the top to let out gas but not let vapour escape. You measure the change in results.
How can you measure increasing volume of gas given off?
If the reaction produces a gas you can use a gas syringe added to a reaction mixture in a conical flask or you can get a measuring cylinder filled with water and watch as the gas displaces the water.
How to calculate mean rate of reaction?
mean rate of reaction=quantity of reactant used/time
or quantity of product formed/time
What is collision theory?
When reactions only take place when the particles of reactants come together. They need to bump into each other with enough energy to cause a reaction to take place.
What is activation energy?
It is the minimum amount of energy that particles must have before they can react.
What are the 5 factors affecting rate of reaction?
Surface area, concentration, temperature, pressure and catalysts
How does surface area impact rate of reaction?
If there is a large lump of reactant, then the reactant will react slowly as less is in contact with the other reactant and if it is in small lumps then more area will be in contact with the other reactant.
How does temperature impact rate of reaction?
Particles collide more often and with more energy. An increased proportion of particles exceeding the activation energy has a greater effect than the increased frequency of collisions.
How does pressure and concentration impact the rate of reaction?
Pressure and concentration, if high, will result in more collisions.
