Reaction rate

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The reaction rate of a chemical reaction is the speed of production of productss from reactants. The rate value is always positive. Reaction rate is expressed in the formula:

In this equation, where [A] is the molar concentration of the reactant (there may be several), n is the order of the reaction,, and k is a constant. Order establishes the mathematical relation of concentration to rate. For instance, in a second-order reaction, if the concentration doubles, the rate quadruples.

When there are is more than one reactant involved in a reaction, the rate is simply the product of all of the reactants and their orders:

Rate is often expressed in the units ^mol/_Ls.

There are several factors that affect the rate of reaction:

Temperature: Conducting a reaction at a higher temperature puts more energy into the system and increases the reaction rate. In general, the reaction rate doubles for every 10 degrees Celcius increase in temperature.
Order: Clearly the order of the reaction has a major effect on its rate. The order of a reaction is found experimentally, and, for most basic reactions, is an integer value.
A catalyst: The presence of a catalyst increases the reaction rate by lowering the activation energy of the reaction.