# What is the equilibrium equation in chemistry? Is it different from the regular equation?

##### 2 Answers

They are the same thing.

#### Explanation:

We call the short-hand notation for a chemical reaction an “equation” because it does involve “balancing” both sides and it is thus related to the mathematical equation. HOWEVER, it is not an equation in the mathematical sense, but a description of the equilibrium conditions of a chemical reaction.

In many cases the “reaction” proceeds primarily to the products, but even in “complete” reactions there will remain residual amounts of the reactants due to the “equilibrium” requirements of chemical interactions.

“Equilibrium constants”, including pH and solubilities are measures of the degree of “completion” or shift of a reaction from one side of the equation to the other.

ALL chemical "equations" (reactions) are reversible, although the energy requirements may be excessive and make the actual event practically impossible.

For the reaction at equilibrium,

#### Explanation:

There is a

And a

So at equilibrium,

And on rearrangement,

And we call the quotient,

And thus we write the familiar equilibrium expression:

And thus large values of