Paper 2 Flashcards
What is the rate of a reaction?
How fast the reactants are changed into products
What are three units for the rate of a reaction?
g/s, cm^3/s or mol/s
Give 2 examples of a slow rates of a reaction
- Chemical weathering (acid rain damage to limestone buildings)
- Rusting of iron
Give an example of a moderate speed reaction
Magnesium reacting with an acid to produce a gentle stream of bubbles
Give an example of a fast reaction
Burning. Explosions are fast and release a lot of gas
How can we find a speed of a reaction
Record the amount of product formed, or used up over time
What does steep lines on the rate of reaction graph mean?
That the rate of reaction is getting faster
What do the quickest reactions look like on a graph?
They have the steepest lines and become flat in the least time
What is collision theory?
Chemical reactions can occur only when reacting particles collide with each other and with sufficient energy
What does the rate of a chemical reaction depend on?
Collision frequency and energy transferred
What is collision frequency?
How often reacting particles collide.
What is energy transferred during a collision?
Particles have to collide with enough energy for the collision to be successful
What is activation energy?
The minimum amount of energy that particles need to react
What does the rate of reaction depend on?
Temperature
Surface area
Concentration of solution/pressure
Presence of catalyst
What does increasing the temperature do to the rate of reaction?
When the temperature is increased the particles move faster. The faster they move the more energy they have.
What does increasing the concentration do to the reaction?
The reacting particles will be closer together
What does increasing pressure to do the rate of reaction?
The same number of particles occupy a smaller space. That means that the particles will collide more often
What does increasing the surface area due to the rate of reaction?
