Calcium iodide

Calcium iodide (chemical formula CaI₂) is the ionic compound of calcium and iodine. This colourless deliquescent solid is a salt that is highly soluble in water. Its properties are similar to those for related salts, such as calcium chloride. It is used in photography. It is also used in cat food as a source of iodine.

Reactions

Henri Moissan first isolated pure calcium in 1898 by reducing calcium iodide with pure sodium metal:

CaI₂ + 2 Na → 2 NaI + Ca

Calcium iodide can be formed by treating calcium carbonate, calcium oxide, or calcium hydroxide with hydroiodic acid:

CaCO₃ + 2 HI → CaI₂ + H₂O + CO₂

Calcium iodide slowly reacts with oxygen and carbon dioxide in the air, liberating iodine, which is responsible for the faint yellow color of impure samples.

2 CaI₂ + 2 CO₂ + O₂ → 2 CaCO₃ + 2 I₂

References

HI +H

He

LiI

BeI2

BI3 +BO3

CI4 +C

NI3 NH4I +N

I2O4 I2O5 I2O6 I4O9

IF IF3 IF5 IF7

Ne

NaI

MgI2

AlI AlI3

SiI4

PI3 P2I4 +P PI5

S2I2

ICl ICl3

Ar

KI

CaI2

ScI3

TiI2 TiI3 TiI4

VI2 VI3

CrI2 CrI3 CrI4

MnI2

FeI2 FeI3

CoI2

NiI2 -Ni

CuI

ZnI2

GaI GaI3

GeI2 GeI4 +Ge

AsI3 As2I4 +As

Se

IBr IBr3

Kr

RbI RbI3

SrI2

YI3

ZrI2 ZrI3 ZrI4

NbI4 NbI5

MoI2 MoI3

TcI3

RuI3

RhI3

PdI2

AgI

CdI2

InI InI3

SnI2 SnI4

SbI3 +Sb

TeI4 +Te

I− I

Xe

CsI CsI3

BaI2

LuI3

HfI3 HfI4

TaI4 TaI5

WI2 WI3 WI4

ReI3 [[Rhenium tetraiodide|Template:Chem/link]]

OsI Template:Chem2 Template:Chem2

IrI3 [[Iridium tetraiodide|Template:Chem/link]]

PtI2 PtI4

AuI AuI3

Hg2I2 HgI2

TlI TlI3

PbI2

BiI3

PoI2 PoI4

AtI

Rn

Fr

RaI2

Lr

Rf

Db

Sg

Bh

Hs

Mt

Ds

Rg

Cn

Nh

Fl

Mc

Lv

Ts

Og

↓

LaI2 LaI3

CeI2 CeI3

PrI2 PrI3

NdI2 NdI3

PmI3

SmI2 SmI3

EuI2 EuI3

GdI2 GdI3

TbI3

DyI2 [[Dysprosium(III) iodide|Template:Chem/link]]

HoI3

ErI3

TmI2 TmI3

YbI2 YbI3

AcI3

ThI2 ThI3 ThI4

PaI4 PaI5

UI3 UI4

NpI3

PuI3

AmI2 AmI3

CmI3

[[Berkelium(III) iodide|Template:Chem/link]]

[[Californium(II) iodide|Template:Chem/link]] [[Californium(III) iodide|Template:Chem/link]]

EsI2 EsI3

Fm

Md

No