Lithium sulfate

Lithium sulfate

Names
IUPAC name Lithium sulfate
Other names Lithium sulphate
Identifiers
CAS Number	10377-48-7 Y 10102-25-7 (monohydrate) N
3D model (Jmol)	Interactive image
ChemSpider	59698 N
ECHA InfoCard	100.030.734
PubChem CID	66320
RTECS number	OJ6419000
UNII	[https://fdasis.nlm.nih.gov/srs/srsdirect.jsp?regno=919XA137JK Li HSO4 919XA137JK Li HSO4] N
InChI InChI=1S/2Li.H2O4S/c;;1-5(2,3)4/h;;(H2,1,2,3,4)/q2*+1;/p-2 N Key: INHCSSUBVCNVSK-UHFFFAOYSA-L N InChI=1/2Li.H2O4S/c;;1-5(2,3)4/h;;(H2,1,2,3,4)/q2*+1;/p-2 Key: INHCSSUBVCNVSK-NUQVWONBAF
SMILES [Li+].[Li+].[O-]S(=O)(=O)[O-]
Properties
Chemical formula	Li2SO4
Molar mass	109.94 g/mol
Appearance	White crystalline solid, hygroscopic
Density	2.221 g/cm3 (anhydrous) 2.06 g/cm3 (monohydrate)
Melting point	859 °C (1,578 °F; 1,132 K)
Boiling point	1,377 °C (2,511 °F; 1,650 K)
Solubility in water	monohydrate: 34.9 g/100 mL (25 °C) 29.2 g/100 mL (100 °C)
Solubility	insoluble in absolute ethanol, acetone and pyridine
Magnetic susceptibility (χ)	−-40.0·10−6 cm3/mol
Refractive index (nD)	1.465 (β-form)
Thermochemistry
Specific heat capacity (C)	1.07 J/g K
Std molar entropy (So298)	113 J/mol K
Std enthalpy of formation (ΔfHo298)	−1436.37 kJ/mol
Gibbs free energy (ΔfG˚)	-1324.7 kJ/mol
Hazards
NFPA 704	0 1 0
Lethal dose or concentration (LD, LC):
LD50 (median dose)	613 mg/kg (rat, oral)
Related compounds
Other cations	Sodium sulfate Potassium sulfate
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
N  (what is YN ?)
Infobox references

Li HSO4 919XA137JK

Lithium sulfate is a white inorganic salt with the formula Li₂SO₄. It is the lithium salt of sulfuric acid.

Lithium sulfate is soluble in water, though it does not follow the usual trend of solubility versus temperature — its solubility in water decreases with increasing temperature, as its dissolution is an endothermic process. This property is shared with few inorganic compounds, such as the lanthanoid sulfates.

Lithium sulfate crystals, being piezoelectric, are also used in ultrasound-type non-destructive testing because they are very efficient sound generators. However, they do suffer in this application because of their water solubility.

Since it has hygroscopic properties, the most common form of lithium sulfate is lithium sulfate monohydrate. Anhydrous Lithium sulfate has a density of 2.22 g/cm³ but, weighing lithium sulfate anhydrous can become cumbersome as it must be done in a water lacking atmosphere.

Lithium Sulfate has pyroelectric properties. When aqueous Lithium sulfated is heated, the electrical conductivity also increases. The molarity of Lithium sulfate also plays a role in the electrical conductivity; optimal conductivity is achieved at 2M and then decreases.

When solid lithium sulfate is dissolved in water it has an endothermic disassociation. This is different than sodium sulfate which is has an exothermic disassociation. The exact energy of disassociation is difficult to quantify as it seems relative to the mols of the salt added. Small amounts of dissolved lithium sulfate have a much greater temperature change than large amounts.

Lithium sulfate has two different crystal phases. In common phase II form, Lithium sulfate has a sphenoidal monoclinic crystal system that has edge lengths of a = 8.23Å b = 4.95Å c = 8.47Å β = 107.98°. When lithium sulfate is heated passed 130 ℃ it changes to a water free state but retains its crystal structure. It is not until 575 ℃ when there is a transformation from phase II to phase I. The crystal structure changes to a face centered cubic crystal system, with an edge length of 7.07Å. During this phase change, the density of Lithium Sulfate changes from 2.22 to 2.07 g/cm³.