Flashcards in Mrs Sedgley F334 Deck (10)
Explain what is meant by a chemical being first order
As the concentration of the chemical doubles, the rate of reation also doubles, as long as all other chemicals have constant concentrations
Explain what is meant by a chemcial being second order
As the concentration of the chemical doubles, the rate of reaction quadrouples, as long as all other chemicals have constant concentrations
If the rate of a reaction is not affected by the use of a chemical what order is that chemical? And is it shown in the rate equation?
Not included in the rate equation
How is the order of each chemical in a reaction caluclated?
Change the concentration of one reactant, and keep the others in excess / constant concentrations (so they have no affect)
Plot a graph of the initial rates (conc / time)
Calculate the half life
If the half life is equal = First order
If the half life doubles = Second order
If there is no half life = Zero order
What is the rate determining step (RDS) of a reaction?
The slowest step in the reaction, and so limits the rate
What does the order of each chemical tell us about the RDS?
The number of molecules of reactant that are used
Eg, [O2]2 = 2O2
True or false? If a chemical is in the rate equation, it is also in the RDS?
What is Competitive inhibition in terms of enzymes?
When a molecule has a similar shape to the real substrate , and can bind to the active site, and so blocks the real subtrate from binding (so reduces the rate of reaction)
If in a reaction, involving an enzyme, has a low substrate concentration, what is the Rate equation / RDS?
Rate = k[E] [S]
RDS = E + S >>> ESC