Advanced Rates Of Reaction Flashcards
What is a first order reaction
When the this substance doubles so does rate (2little 1)
What is a second order reaction
When this increases by 2 the rate is increased by a factor of 2
What is the rate equation
Rate=K (A)Order X (B)Order
What is overall order
Sum of orders
Concentration time graph
Pleated through continuous monitoring
Gas collection
Mass loss
How to do rate colorimeter
Wave length light controlled with filter
Amount of light absorbed is measured
Eg CH3COCH3 + I2 -> Ch3CoCh2I +H+ + I-
Orange/ brown colour fades
In a concentration time graph what is rate
Grading
In a concentration time graph what shape is 0 order
Straight down
In a concentration time graph what is 1st order
Curved down
In a concentration time graph what is second order
More curved down
In a 1st order reaction is half life constant
Yes
How to find K from half life
K= Ln(2)/half life
What is a half life
Amount of time required for half of the reactant to be used up
How to find K from concentration time graph
Tangent at value = rate
Re arrange rate equation
How to find K from a rate concentration graph
K = gradient
Rate concentration graph what does zero order look like
Straight horizontal line
Rate concentration graphs what does 1st order look like
Straight up
Rate concentration graph what does second order look like
Curved up
How to get K form a second order reactions
Square results
Log graphs Y and X axis
Y= log rate X = log concentration
Y=mx + c for rate
Log(rate)= M log(A) + Log(K)
Initial rates method
Start reaction at 0
Obtained by clock reaction
Initial rate is proportional to 1/t
H2O2 +2I- (Aq) + 2 H+ -> I2 + 2 H2O
With starch black to colourless
How accurate is the iodine clock
You have to assume average rate of reaction
What is the rate determining step
The slowest step
What does the order shoe is rate determining step
Ratio
As temperature increases what does rate do
Increase
Where to find Arhenious equation
Data sheet (this includes Ln one)
Arehenious y=mx +c
Ln(K) = -ea 1/t + Lna
R
Calculating activation energy from Arehenious graph
Gas constant times by gradient
What does A equal
E to the power of Ln(a)