Topic 6: Chemical Kinetics Flashcards
1
Q
Rate of Reaction
A
- the change i concentration of reactants or products per unit time
- SI Unit: mol/dm^3 s^1
2
Q
What methods can be used to measure the rate of reaction?
A
- change in volume
- change in mass
- change in transmission of light
- change in concentration
- change in conductivity
- non-continuous methods
3
Q
Methods to Measure the Rate of Reaction
Change in Volume
A
4
Q
Methods to Measure the Rate of Reaction
Change in Mass
A
5
Q
Methods to Measure the Rate of Reaction
Change in Transmission of Light
A
6
Q
Methods to Measure the Rate of Reaction
Change in Concentration
A
7
Q
Methods to Measure the Rate of Reaction
Change in Conductivity
A
8
Q
Methods to Measure the Rate of Reaction
Non-continuous Methods
A
9
Q
What are the 3 ways that rate of reaction can be expressed in?
A
- average rate
- instantaneous rate
- initial rate
10
Q
Average Rate
Definition & Formula
A
- a measure of the change in concentration of reactant or product in a given time interval, t.
- average rate = △c/△t
△c =change in concentration of reactant or product
△t = time interval
11
Q
Instantaneous Rate
Definition
A
- the rate at a particular time
- determined by finding the slope of the tangent to the concentration vs time curve at that time
12
Q
Initial Rate
A
- is the instantaneous rate at the start of the reaction
- when t = t0, the instantaneous rate = initial rate
- initial rate = △y/△x
13
Q
Rate Equation
A
- is a mathematical differential expression, which shows rate expressed in terms of concentration
- for example, in the reaction A + B → C + D, a rate equation can be writen as follows:
rate = - d[A]/dt = - d[B]/dt = + d[C]/dt = + d[D]/dt - if there is a coefficit in front of the terms, just turn the cofficiet into a fraction and multiply it with the values, for example: xA + yB → qC + pD, will have a rate reaction written like so:
rate = - 1/x ⋅ d[A]/dt = - 1/y ⋅ d[B]/dt = + 1/q ⋅ d[C]/dt = + 1/p ⋅ d[D]/dt
14
Q
Kinetic - molecular theory of gas
A
- The particles in a gas are in constant, random motion
- The combined volume of the particles is negligible
- The particles exert no forces on one another
- Any collisions between the particles are completely elastic
- The average kinetic energy of the particles is proportional to the temperature in kelvins.
15
Q
What conditions need to be fulfilled in
A
