H

Heterogeneous Equilibria

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Also Known AsHeterogeneous equilibrium, multi-phase equilibrium, solid-gas equilibrium

What is Heterogeneous Equilibria?

Heterogeneous equilibria are chemical equilibria in which the reactants and products are present in more than one phase (e.g., solid, liquid, and gas). The equilibrium expression for such systems excludes the concentrations of pure solids and pure liquids, as their activities are defined as unity (their concentration is constant). This simplification is key to working with heterogeneous equilibrium expressions.

Properties & Characteristics

Example: CaCO₃(s) ⇌ CaO(s) + CO₂(g) — Kp = P(CO₂). Pure solids and liquids: activity = 1 (excluded from K expression). Kc and Kp related by: Kp = Kc(RT)^Δn. Common examples: dissolution equilibria, saturated solutions (Ksp), gas-solid reactions. Equilibrium constant depends only on temperature.

Uses & Applications

Industrial chemical processes (Haber process involves heterogeneous phases). Solubility product calculations. Understanding geological processes (carbonate dissolution). Metallurgical roasting reactions. Catalyst surface reactions. Environmental chemistry (mineral dissolution).

Safety Information

Safety varies by specific reaction. Gas-phase products from solid decomposition may be toxic. High-temperature heterogeneous reactions present fire/explosion hazards. Molten metal and liquid-solid interfaces present burn hazards.

Always consult the SDS/MSDS before handling any chemical. This information is for educational purposes only.

Key Facts

Term Heterogeneous Equilibria
Synonyms Heterogeneous equilibrium, multi-phase equilibrium, solid-gas equilibrium

Frequently Asked Questions

Heterogeneous equilibria are chemical equilibria in which the reactants and products are present in more than one phase (e.g., solid, liquid, and gas). The equilibrium expression for such systems excludes the concentrations of pure solids and pure liquids, as their activities are defined as unity (their concentration is constant). This simplification is key to working with heterogeneous equilibrium expressions.

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