What is an ICE table?

ICE stands for Initial, Change, Equilibrium. It is a structured method for tracking concentration changes as a reaction reaches equilibrium. You write starting concentrations, express the change in terms of x, then solve for x using the equilibrium expression.

Ka is the acid dissociation constant. It quantifies how completely a weak acid donates a proton in water. A larger Ka means a stronger acid that dissociates more.

Kb is the base dissociation constant. It measures how much a weak base accepts a proton from water. Larger Kb means stronger base.

When is the 5% approximation valid?

When x (the amount that dissociates) is less than 5% of the initial concentration, you can approximate [A] ≈ C₀ − x ≈ C₀. This tool always solves exactly via the quadratic formula and flags whether the approximation would have been valid.

Can I use this for polyprotic acids?

This tool handles single-step equilibria (one Ka or Kb). For polyprotic acids, only the first dissociation step typically dominates; use this tool for that step.

What units should I use?

Concentrations should be in molarity (mol/L). Ka and Kb are dimensionless equilibrium constants expressed in the same molarity units.

Equilibrium Concentration Calculator

Name: Equilibrium Concentration Calculator
Availability: InStock
Author: Nham Vu

Enter initial concentrations and Ka or Kb to compute equilibrium concentrations via an ICE table.

Reaction Setup

Reaction Type

Ka (acid dissociation constant)

Initial [HA] (mol/L)

Initial [A⁻] (mol/L) — usually 0

ICE Table

Step	[HA]	[H⁺]	[A⁻]
Initial	—	—	—
Change	—	—	—
Equilibrium	—	—	—

Summary

Enter initial concentrations and Ka or Kb to compute equilibrium concentrations via an ICE table.

How it works

Enter the equilibrium constant (Ka or Kb) for your reaction.
Input the initial concentrations of the reactant (acid or base) and any products.
The tool builds an ICE table showing Initial, Change, and Equilibrium rows.
It solves the equilibrium expression algebraically or via iteration.
Equilibrium concentrations are displayed along with percent dissociation.

Use cases

Calculate the equilibrium concentrations for a weak acid dissociation.
Find equilibrium concentrations for a weak base ionization.
Verify ICE table work for chemistry homework and exams.
Explore how changing initial concentration affects equilibrium.
Compute percent dissociation of a weak acid or base.
Check whether the 5% approximation is valid for a given system.

Frequently Asked Questions

Last updated: 2026-06-18 · Reviewed by Nham Vu