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hydrogen iodide

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hydrogen iodide

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Also known as hydroiodic acid, HI

chemical compound

Chemical data

Formula
HI
Molecular weight
127.9124 g/mol
IUPAC name
hydron iodide
SMILES
[H+].[I-]
InChIKey
XMBWDFGMSWQBCA-UHFFFAOYSA-N
Polar surface area
0 Ų
H-bond donors
1
H-bond acceptors
1
Formal charge
0

via PubChem

Wikidata facts

Subclass of
hydrogen halide
Has part
iodine
Mass
127.9123
Show 14 more facts
chemical formula
HI
canonical SMILES
I
speed of sound
157
different from
hydroiodic acid
melting point
-50.77
boiling point
-35.55
decomposition point
300
standard enthalpy of formation
26.6
pKa
-11
Commons category
Hydrogen iodide
standard molar entropy
206.6
found in taxon
Homo sapiens
ionization energy
10.39
electric dipole moment
0.448
Sources (5)

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Encyclopedic overview

Hydrogen iodide (HI) is a diatomic molecule and hydrogen halide. Aqueous solutions of HI are known as hydroiodic acid or hydriodic acid, a strong acid. Hydrogen iodide and hydroiodic acid are, however, different in that the former is a gas under standard conditions, whereas the latter is an aqueous solution of the gas. They are interconvertible. HI is used in organic and inorganic synthesis as one of the primary sources of iodine and as a reducing agent.

Properties of hydrogen iodide

Excerpted from Wikipedia’s “hydrogen iodide” article, available under the CC BY-SA 4.0 licence.

Gallery (6)