Hello Everyone, thanks for clicking on this post. Today I'll be discussing reaction orders.
Why you should understand Reaction Orders: Reaction orders are very helpful when trying to describe the kinetics of a reaction.
Key Ideas
- The Definition of Reaction Order
- The three different reaction orders
- Important Note
The Definition of Reaction Order
Reaction orders describe the relationship between a reactant and the rate of the reaction. More specifically, the reaction order tells us how the reactant increases or decreases the rate of reaction.
It's important to understand that reaction orders can only be determined from experimental data like the example data I've added below.
By comparing the changes in concentration to the changes in rates, you can determine the reaction order with respect to one particular reactant.
The three different reaction orders
There are three different reaction orders: zero, first, and second. Below is a summary of how each reaction order relates to the rate of the reaction.
Zero order reactant- As the concentration of the reactant changes by a factor of 3 (three is just an example, the concentrations can be changed by any factor), then the rate doesn't change. In other words, a zero order reactant has no impact on the rate.
First order reactant- As the concentration is multiplied by 3, the rate is also multiplied by a factor of 3. In other words, whatever factor the concentration changes by is the same factor that the rate changes by. This is because 3 raised to the first power is 3.
Second Order reactant- As the concentration changes by 3, then the rate changed by a factor of 9. Because 9 is 3 raised to the second power. In other words, if a concentration changes by a factor then the rate changed by that factor raised to the second power.
Important Note
Reaction order can only be determined experimentally. The reaction orders do not come from the coefficients in the balanced reaction.
Summary
- Reaction orders describe the relationship between a reactant and the rate of the reaction.
- It's important to understand that reaction orders can only be determined from experimental data.
- There are three different reaction orders: zero, first, and second.
- The reaction orders do not come from the coefficients in the balanced reaction.
I hope you've found this post on Reaction Orders helpful. If you have any questions feel free to comment on this post, email me, or comment on the video I've linked below.
- Saren
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