Rate of reaction Flashcards
What is the rate of reaction?
How quickly the reactants turn into the product
What is the calculation to figure out mean rate of reaction?
Mean rate = change in quantity of product or reactant / time taken
Explain an experiment to measure change in mass related to the rate of reaction
Place a reaction mixture inside a conical flask
Place a cotton wool bung in the top of the flask
Place on mass balance
As the reaction proceeds, the gaseous product is given off the mass of the flask will decrease
Calculate the rate using change in mass / time taken
What is the unit for rate for mass
g/s
Explain an experiment that uses the volume of gas produced to workout rate of the reaction
The reaction mixture inside a clinical flask is connected to a measuring cylinder submerged in water by a rubber tubing
start a stop watch
As the reaction proceeds, the gas is collected
time how long it takes for all water to disappear
The calculation for the rate is volume of gas produced / time taken
What is the unit for rate for volume?
cm cubed/s
How to calculate the mean rate between two points in time
Find the mass at both given time points
Calculate the difference between those two masses
Calculate the difference in time of the two points
Divide the change in mass by the change in time
How to find mean rate at specific time
Draw a tangent and calculate its gradient
What is the collision theory?
Chemical reactions occur, only when the reactant particles collide with sufficient energy to react
What is activation energy?
The minimum amount of energy needed for colliding particles to have before a reaction will take place
How to increase rate of reaction
Increasing the frequency of collisions
Increase in the energy of the particles when they collide
Explain how increasing the temperature will affect the rate of reaction
Particles move faster, leading to more frequent collisions
Particles have more energy, so more collisions result in a reaction
How does increasing the concentration of solution affect the rate of reaction?
There are more reactant particles in the reaction mixture, so collisions become more frequent
How does increasing the pressure of gases affect the rate of reaction?
Less space between particles means more frequent collision
How does increasing the surface area of solids affect the rate of reaction?
Only the reactant particles on the surface of a solid are able to collide and react
The greater the surface area, the more reactive particles are exposed, leading to more frequent collisions
