R2.2 (The rate of chemical change) Flashcards
1
Q
Reaction rate
A
speed at which reactents turn into products
2
Q
Relevance of reaction rate
A
- Industrial processes (want to know how to produce more & faster)
3
Q
Ways in which rate of reaction can be measured
A
- prodcut produced over time
- reactent used over time
4
Q
why reactions stop
A
- concentration of reactents decreases
- decreases frequency of collisions
- reaction slows down
5
Q
calculating instantaneous rate of change (derivative)
A
- draw a tangent to the point on the curve
- construct a right angled triangle with the tangent as te hypothenuse (as large as possible)
- calculate gradient of tangent (Δy/Δx)
6
Q
reaction rate formula
A
Δ quantity/ Δ time
7
Q
collision theory
A
in order for a chemical reaction to occur the particles of the reactents must first collide
8
Q
Requirements for successful collisions
A
- collision geometry must be correct
- reactent particles must have the right amount of energy
9
Q
collision geometry
A
position and coordination of particles as they collide and interact with eachother
10
Q
activation energy
A
minimum amount of energy required for a reaction to commence
11
Q
A
11
Q
factors affecting rate of reaction
In this case to increase rate
A
- concentration= more particles in given volume = more collisions
- pressure= more particles in given volume colliding with eachother
- particle size = smaller particles = larger overall SA as more surfaces are exposed = more collisions
- temperature = increased Ekin = increased frequency and force
- catalyst = lowers activation energy
11
Q
A
