Hydroiodic acid

Properties
General
Name	Hydrogen iodide
Chemical formula	H I
Appearance	Colourless gas
Physical
Formula weight	127.91 amu
Melting point	222.4 K (-50.8 °C
Boiling point	237.77 K (-35.38 °C)
Density	1.7 ×10³ kg/m³ (liquid)
Solubility	42.5 g in 100g water
Thermochemistry
Δ_fH⁰_gas	? kJ/mol
Δ_fH⁰_liquid	? kJ/mol
Δ_fH⁰_solid	? kJ/mol
S⁰_{gas, 1 bar}	? J/mol·K
S⁰_{liquid, 1 bar}	? J/mol·K
S⁰_solid	? J/mol·K
Safety
Ingestion	Toxic, can be fatal.
Inhalation	Fumes may be fatal. Do not give unprotected mouth-to-mouth resuscitation.
Skin	May cause severe burns.
Eyes	Extremely dangerous.
SI units were used where possible. Unless otherwise stated, standard conditions were used. Disclaimer and references

The chemical compound hydroiodic acid is a highly acidic aqueous solution of hydrogen iodide (H I). It is highly corrosive and should be handled only with appropriate precautions. Hydroiodic acid is a commonly used chemical reagent and is one of the strong acids that ionize completely in aqueous solution. Concentrated hydroiodic acid has a pH of less than 1.