1. What is the Reaction Quotient?

The reaction quotient (Q) measures the relative amounts of products and reactants present during a reaction at a particular point in time. It helps determine the direction in which a reaction will proceed to reach equilibrium.

2. How Does the Calculator Work?

The calculator uses the reaction quotient equation:

Where:

• \( [products] \) — Concentration of products (mol/L)
• \( [reactants] \) — Concentration of reactants (mol/L)

Explanation: The reaction quotient is calculated by dividing the product of the concentrations of the reaction products by the product of the concentrations of the reactants.

3. Importance of Q Calculation

Details: Comparing Q to the equilibrium constant (K) predicts reaction direction:

• Q < K: Reaction proceeds forward (more products form)
• Q = K: System is at equilibrium
• Q > K: Reaction proceeds in reverse (more reactants form)

4. Using the Calculator

Tips: Enter concentrations in mol/L. Reactants concentration must be greater than zero. For multiple reactants/products, multiply their concentrations first before entering.

5. Frequently Asked Questions (FAQ)

Q1: What's the difference between Q and K?
A: Q describes any point in the reaction, while K describes only the equilibrium state.

Q2: How do I use Q with multiple reactants/products?
A: Multiply concentrations of each species raised to their stoichiometric coefficients before dividing.

Q3: What units should I use?
A: Molarity (mol/L) is standard, but any consistent units will work as Q is dimensionless.

Q4: How does Q relate to Gibbs free energy?
A: ΔG = ΔG° + RT lnQ, where ΔG° is the standard Gibbs free energy change.

Q5: Can Q be negative?
A: No, since concentrations are always positive or zero, Q is always positive or zero.