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Names | |
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IUPAC name Lithium oxide | |
Other names Lithia Kickerite Dilithium Monoxide Dilithium Oxide | |
Identifiers | |
3D model (JSmol) | |
ChemSpider | |
ECHA InfoCard | 100.031.823 |
PubChem CID | |
RTECS number |
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UNII | |
CompTox Dashboard (EPA) | |
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Properties | |
Li 2O | |
Molar mass | 29.88 g/mol |
Appearance | white solid |
Density | 2.013 g/cm3 |
Melting point | 1,438 °C (2,620 °F; 1,711 K) |
Boiling point | 2,600 °C (4,710 °F; 2,870 K) |
Reacts to form LiOH | |
log P | 9.23 |
Refractive index (nD) | 1.644 [1] |
Structure | |
Antifluorite (cubic), cF12 | |
Fm3m, No. 225 | |
Tetrahedral (Li+); cubic (O2−) | |
Thermochemistry | |
Heat capacity (C) | 1.8105 J/g K or 54.1 J/mol K |
Std molar entropy (S⦵298) | 37.89 J/mol K |
Std enthalpy of formation (ΔfH⦵298) | -20.01 kJ/g or -595.8 kJ/mol |
Gibbs free energy (ΔfG⦵) | -562.1 kJ/mol |
Hazards | |
Occupational safety and health (OHS/OSH): | |
Main hazards | Corrosive, reacts violently with water |
NFPA 704 (fire diamond) | |
Flash point | Non-flammable |
Related compounds | |
Other anions | Lithium sulfide Lithium selenide Lithium telluride Lithium polonide |
Other cations | Sodium oxide Potassium oxide Rubidium oxide Caesium oxide |
Lithium peroxide Lithium superoxide | |
Related compounds | Lithium hydroxide |
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). |
Lithium oxide (Li
2 O) or lithia is an inorganic chemical compound. It is a white solid. Although not specifically important, many materials are assessed on the basis of their Li2O content. For example, the Li2O content of the principal lithium mineral spodumene (LiAlSi2O6) is 8.03%. [2]
Lithium oxide forms along with small amounts of lithium peroxide when lithium metal is burned in the air and combines with oxygen at temperatures above 100 °C: [3]
Pure Li
2O can be produced by the thermal decomposition of lithium peroxide, Li
2O
2, at 450 °C [3] [2]
Solid lithium oxide adopts an antifluorite structure with four-coordinated Li+ centers and eight-coordinated oxides. [4]
The ground state gas phase Li
2O molecule is linear with a bond length consistent with strong ionic bonding. [5] [6] VSEPR theory would predict a bent shape similar to H
2O.
Lithium oxide is used as a flux in ceramic glazes; and creates blues with copper and pinks with cobalt. Lithium oxide reacts with water and steam, forming lithium hydroxide and should be isolated from them.
Its usage is also being investigated for non-destructive emission spectroscopy evaluation and degradation monitoring within thermal barrier coating systems. It can be added as a co-dopant with yttria in the zirconia ceramic top coat, without a large decrease in expected service life of the coating. At high heat, lithium oxide emits a very detectable spectral pattern, which increases in intensity along with degradation of the coating. Implementation would allow in situ monitoring of such systems, enabling an efficient means to predict lifetime until failure or necessary maintenance.
Lithium metal might be obtained from lithium oxide by electrolysis, releasing oxygen as by-product.
Lithium oxide absorbs carbon dioxide forming lithium carbonate:
The oxide reacts slowly with water, forming lithium hydroxide:
The alkali metals consist of the chemical elements lithium (Li), sodium (Na), potassium (K), rubidium (Rb), caesium (Cs), and francium (Fr). Together with hydrogen they constitute group 1, which lies in the s-block of the periodic table. All alkali metals have their outermost electron in an s-orbital: this shared electron configuration results in their having very similar characteristic properties. Indeed, the alkali metals provide the best example of group trends in properties in the periodic table, with elements exhibiting well-characterised homologous behaviour. This family of elements is also known as the lithium family after its leading element.
Inorganic chemistry deals with synthesis and behavior of inorganic and organometallic compounds. This field covers chemical compounds that are not carbon-based, which are the subjects of organic chemistry. The distinction between the two disciplines is far from absolute, as there is much overlap in the subdiscipline of organometallic chemistry. It has applications in every aspect of the chemical industry, including catalysis, materials science, pigments, surfactants, coatings, medications, fuels, and agriculture.
In chemistry, a hydride is formally the anion of hydrogen (H−), a hydrogen atom with two electrons. The term is applied loosely. At one extreme, all compounds containing covalently bound H atoms are called hydrides: water (H2O) is a hydride of oxygen, ammonia is a hydride of nitrogen, etc. For inorganic chemists, hydrides refer to compounds and ions in which hydrogen is covalently attached to a less electronegative element. In such cases, the H centre has nucleophilic character, which contrasts with the protic character of acids. The hydride anion is very rarely observed.
Potassium oxide (K2O) is an ionic compound of potassium and oxygen. It is a base. This pale yellow solid is the simplest oxide of potassium. It is a highly reactive compound that is rarely encountered. Some industrial materials, such as fertilizers and cements, are assayed assuming the percent composition that would be equivalent to K2O.
Lithium hydroxide is an inorganic compound with the formula LiOH. It can exist as anhydrous or hydrated, and both forms are white hygroscopic solids. They are soluble in water and slightly soluble in ethanol. Both are available commercially. While classified as a strong base, lithium hydroxide is the weakest known alkali metal hydroxide.
Cuprates are a class of compounds that contain copper (Cu) atom(s) in an anion. They can be broadly categorized into two main types:
Cobalt(II) chloride is an inorganic compound, a salt of cobalt and chlorine, with the formula CoCl
2. The compound forms several hydrates CoCl
2·nH
2O, for n = 1, 2, 6, and 9. Claims of the formation of tri- and tetrahydrates have not been confirmed. The anhydrous form is a blue crystalline solid; the dihydrate is purple and the hexahydrate is pink. Commercial samples are usually the hexahydrate, which is one of the most commonly used cobalt salts in the lab.
Ozonide is the polyatomic anion O−3. Cyclic organic compounds formed by the addition of ozone to an alkene are also called ozonides.
Basic oxides are oxides that show basic properties, in opposition to acidic oxides. A basic oxide can either react with water to form a base, or with an acid to form a salt and water in a neutralization reaction.
Lithium aluminate, also called lithium aluminium oxide, is an inorganic chemical compound, an aluminate of lithium. In microelectronics, lithium aluminate is considered as a lattice matching substrate for gallium nitride. In nuclear technology, lithium aluminate is of interest as a solid tritium breeder material, for preparing tritium fuel for nuclear fusion. Lithium aluminate is a layered double hydroxide (LDH) with a crystal structure resembling that of hydrotalcite. Lithium aluminate solubility at high pH is much lower than that of aluminium oxides. In the conditioning of low- and intermediate level radioactive waste (LILW), lithium nitrate is sometimes used as additive to cement to minimise aluminium corrosion at high pH and subsequent hydrogen production. Indeed, upon addition of lithium nitrate to cement, a passive layer of LiH(AlO
2)
2 · 5 H
2O is formed onto the surface of metallic aluminium waste immobilised in mortar. The lithium aluminate layer is insoluble in cement pore water and protects the underlying aluminium oxide covering the metallic aluminium from dissolution at high pH. It is also a pore filler. This hinders the aluminium oxidation by the protons of water and reduces the hydrogen evolution rate by a factor of 10.
Lithium peroxide is the inorganic compound with the formula Li2O2. It is a white, nonhygroscopic solid. Because of its high oxygen:mass and oxygen:volume ratios, the solid has been used to remove CO2 from the atmosphere in spacecraft.
Lithium superoxide is an unstable inorganic salt with formula LiO2. A radical compound, it can be produced at low temperature in matrix isolation experiments, or in certain nonpolar, non-protic solvents. Lithium superoxide is also a transient species during the reduction of oxygen in a lithium–air galvanic cell, and serves as a main constraint on possible solvents for such a battery. For this reason, it has been investigated thoroughly using a variety of methods, both theoretical and spectroscopic.
Lithium carbide, Li
2C
2, often known as dilithium acetylide, is a chemical compound of lithium and carbon, an acetylide. It is an intermediate compound produced during radiocarbon dating procedures. Li
2C
2 is one of an extensive range of lithium-carbon compounds which include the lithium-rich Li
4C, Li
6C
2, Li
8C
3, Li
6C
3, Li
4C
3, Li
4C
5, and the graphite intercalation compounds LiC
6, LiC
12, and LiC
18.
Li
2C
2 is the most thermodynamically-stable lithium-rich carbide and the only one that can be obtained directly from the elements. It was first produced by Moissan, in 1896 who reacted coal with lithium carbonate.
Lithium cobalt oxide, sometimes called lithium cobaltate or lithium cobaltite, is a chemical compound with formula LiCoO
2. The cobalt atoms are formally in the +3 oxidation state, hence the IUPAC name lithium cobalt(III) oxide.
The oxidation state of oxygen is −2 in almost all known compounds of oxygen. The oxidation state −1 is found in a few compounds such as peroxides. Compounds containing oxygen in other oxidation states are very uncommon: −1⁄2 (superoxides), −1⁄3 (ozonides), 0, +1⁄2 (dioxygenyl), +1, and +2.
Cobalt(II) hydroxide or cobaltous hydroxide is the inorganic compound with the formula Co(OH)
2, consisting of divalent cobalt cations Co2+
and hydroxide anions OH−
. The pure compound, often called the "beta form" is a pink solid insoluble in water.
The lithium–air battery (Li–air) is a metal–air electrochemical cell or battery chemistry that uses oxidation of lithium at the anode and reduction of oxygen at the cathode to induce a current flow.
Metal peroxides are metal-containing compounds with ionically- or covalently-bonded peroxide (O2−
2) groups. This large family of compounds can be divided into ionic and covalent peroxide. The first class mostly contains the peroxides of the alkali and alkaline earth metals whereas the covalent peroxides are represented by such compounds as hydrogen peroxide and peroxymonosulfuric acid (H2SO5). In contrast to the purely ionic character of alkali metal peroxides, peroxides of transition metals have a more covalent character.
Cobalt compounds are chemical compounds formed by cobalt with other elements.
Gallium compounds are compounds containing the element gallium. These compounds are found primarily in the +3 oxidation state. The +1 oxidation state is also found in some compounds, although it is less common than it is for gallium's heavier congeners indium and thallium. For example, the very stable GaCl2 contains both gallium(I) and gallium(III) and can be formulated as GaIGaIIICl4; in contrast, the monochloride is unstable above 0 °C, disproportionating into elemental gallium and gallium(III) chloride. Compounds containing Ga–Ga bonds are true gallium(II) compounds, such as GaS (which can be formulated as Ga24+(S2−)2) and the dioxan complex Ga2Cl4(C4H8O2)2. There are also compounds of gallium with negative oxidation states, ranging from -5 to -1, most of these compounds being magnesium gallides (MgxGay).