Henry's Law — Definition, Formula, Properties & Uses | AllChemicals | AllChemicals

Q: What is the formula for Henry's Law?

The formula or notation for Henry's Law is: p = kH × c (Henry's law); kH varies with T and gas identity

Formula / Notation	p = kH × c (Henry's law); kH varies with T and gas identity
Also Known As	Henry's law, gas solubility law, Henry constant kH

What is Henry's Law?

A gas law stating that at constant temperature, the solubility of a gas in a liquid is directly proportional to the partial pressure of that gas above the liquid: C = kP. Used to explain carbonation of beverages, oxygen transport in blood, and decompression sickness in divers.

Formula & Notation

p = kH × c (Henry's law); kH varies with T and gas identity

Other Names / Synonyms: Henry's law, gas solubility law, Henry constant kH

Properties & Characteristics

Henry's law states that at constant temperature, the amount of a gas dissolved in a liquid is directly proportional to the partial pressure of that gas above the liquid: p = kH × c (or c = kH × p, depending on convention). Henry's law constant (kH) is specific to each gas-solvent pair and decreases with increasing temperature (gases become less soluble when heated). It applies to dilute solutions and low pressures.

Uses & Applications

Henry's law governs: gas exchange in the lungs (O₂ and CO₂ dissolved in blood), carbonation of beverages (CO₂ dissolved under pressure), decompression sickness in diving (N₂ dissolves at depth, forms bubbles on rapid ascent), environmental fate of volatile organic compounds (volatilisation from water bodies), and design of gas absorption towers.

Safety Information

Decompression sickness ("the bends") from rapid ascent during scuba diving is a direct consequence of Henry's law: N₂ dissolved at depth (high pressure) forms bubbles in blood and tissues upon rapid pressure reduction, causing joint pain, neurological damage, or death. Slow ascent rates and decompression stops mitigate this risk.

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

Key Facts

Term Henry's Law

Formula p = kH × c (Henry's law); kH varies with T and gas identity

Index All "H" terms

Synonyms Henry's law, gas solubility law, Henry constant kH

Frequently Asked Questions

What is Henry's Law?

A gas law stating that at constant temperature, the solubility of a gas in a liquid is directly proportional to the partial pressure of that gas above the liquid: C = kP. Used to explain carbonation of beverages, oxygen transport in blood, and decompression sickness in divers.

What is Henry's Law used for?

Is Henry's Law hazardous?

What is the formula for Henry's Law?

More "H" Terms

Haber Process N₂ + 3H₂ ⇌ 2NH₃ | ΔH = −92 kJ/mol Hafnium Hf Half Cell Half Life Half-Cell E = E° − (RT/nF)lnQ Half-Life A(t) = A₀e^(−λt); t½ = ln2/λ Half-Reaction Halide X⁻ (e.g., F⁻, Cl⁻, Br⁻, I⁻) Halogen F₂, Cl₂, Br₂, I₂, At; Group 17; ns²np⁵ valence configuration Halogenation C-X + Cl₂/Br₂ (hv or AlCl₃) → C-X(halogen); EAS or radical pathway Halogens Hard Acid Hard acid: small, highly charged, low polarisability (e.g., H⁺, Mg²⁺, Al³⁺)

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