Reaction Q Calculator
Calculate the reaction quotient Q.
About Reaction Q Calculator
The reaction quotient for Reaction Q is computed exactly like Keq but at the current concentrations, so comparing Q with Keq shows which direction the reaction must move. Comparing Q and Keq predicts the direction of change without any kinetics.
Formula
Reaction Q
Q = [products] / [reactants]; compare Q with Keq
- Q
- The ratio at the current moment, before equilibrium is reached
Worked example
With the default values below, Reaction Q Calculator returns Reaction Quotient Q of 2.000. Change any input above and every figure here is recalculated in your browser.
Inputs used
- Product concentrationminimum 0
- 2
- Reactant concentrationminimum 0
- 1
- Equilibrium constantminimum 0
- 1.5
Results
- Reaction Quotient Q
- 2.000
- Direction to Equilibrium
- Shifts toward reactants
- Q / Keq
- 1.333
Step by step
- 1Values used
- 2Reaction Q
- 3Reaction Quotient Q= 2.000
- 4Direction to Equilibrium= Shifts toward reactants
- 5Q / Keq= 1.333
Assumptions and limits
- The result is derived only from the 3 inputs listed above. Anything not among them is not part of the calculation.
- In particular, this calculator does not take inflation, tax, fees or charges or compounding frequency into account.
- Figures are rounded for display to 3 decimal places, so totals built from several rounded parts can differ slightly from the unrounded arithmetic.
How these calculators are built and tested is described on the Methodology page. If a figure looks wrong, please report it.
Frequently Asked Questions
How is Reaction Q calculated?
Q = [products] / [reactants]; compare Q with Keq The reaction quotient for Reaction Q is computed exactly like Keq but at the current concentrations, so comparing Q with Keq shows which direction the reaction must move.
Why does Reaction Q matter?
Comparing Q and Keq predicts the direction of change without any kinetics.
What values do I need to enter?
This calculator takes 3 inputs: Product concentration, Reactant concentration, Equilibrium constant. The pre-filled defaults are a realistic starting point — replace them with figures from your own environment for a result you can act on.