Order of Reaction and Reaction Rate Equation

Changing the concentration of a substance in a reaction usually also change the rate of reaction. Rate equation mathematically describes these changes. Order is part of the reaction rate equation. This page introduces and explains the various terms you need to know.
 
rate equation
Measuring the reaction rate

There are several ways to measure the rate of a reaction. For example, if the gas is released in a reaction, we can measure it by calculating the volume of gas released per minute at any given time during the reaction.

Definition This rate can be measured in cm 3 s -1

However, for a more formal and mathematically to determine the rate of a reaction, the rate is usually measured by how fast the concentration of a reactant decreases at any given time.

For example, suppose you had a reaction between two compounds A and B. Suppose that at least one of them is a substance that can be measured concentration-for example, in solution or in the form of gas.



For this we can measure the reaction rate of the reaction by investigating how fast the concentration of, say, A reduced per second.

You might, for example, at the beginning of the reaction, the concentration decreases at a rate of 0.0040 mol dm -3 s -1.

This means that every second A reduced concentration of 0.0040 moles per cubic decimetre. This rate will increase as the reaction of a place.
conclusion

To order rate equations and reaction, the reaction rate is measured by how fast the concentration of a reactant decreases. Units are mol dm -3 s -1