5.1.1 how fast Flashcards
1
Q
rate of reaction
A
change in concentration of a substance in unit time
mol dm-3 s-1
2
Q
rate on graph
A
conc time graph
gradient of tangent to curve
3
Q
initial rate
A
rate at the start of the reaction where it is fastest
4
Q
continuous rate experiments
A
find half lives
if constant, 1st order
is half lives rapidly increase then order is 2nd order
5
Q
rate constant
A
k
rate = k (conc)
increases if we increase temperature
6
Q
arrhenius constant
A
ln K = constant - Ea / RT
Activation energy can be measured from gradient of lnK against 1/T graph
so, Ea = - gradient x R (Gas constant)
convert to kJ mol-1
7
Q
ways to investigate rates of reaction
A
measure change in volume of gas
measure change of mass
8
Q
measure change in volume of gas
A
connect gas syringe to conical flask
9
Q
slowest step
A
rate-determining step
