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Flashcards in Rates of Reaction Deck (9)
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1

How are rates of reaction measured?

By observing the changes in quantities of reactants or products over time

2

Rate =

change in concentration/ time

3

Concentration

-Measured in moldm-3
-units:moldm-3s-1
-[A] means concentration of A

4

Zero order

-When the concentration of a reactant has no effect on the rate.
-Any number raised to the power of zero is 1

5

First order

-A reaction is first order when the rate depends on the concentration raised to the power of one.
-Any change in concentration gives the same change in rate.

6

Second order

A r

7

Second order

-A reaction is second order when the rate depends on the concentration raised to the power of 2
-Any change in concentration changes the rate by the square of the change

8

Overall order

The overall order of reaction gives the overall effect of the concentrations of all reactants on the rate of reaction

9

How are orders determined?

-They are determined experimentally by monitoring how a physical quantity changes over time.
-Orders can't be found from a chemical equation