Sodium superoxide

Sodium superoxide
Names

IUPAC name sodium superoxide
Other names sodium superoxide sodium dioxide
Identifiers
CAS Number	1313-60-6^Y
3D model (JSmol)	Interactive image
ChemSpider	8305406
PubChem CID	61542
RTECS number	WE2860010
UNII	3GSN3JCJ5K^Y
UN number	2547
CompTox Dashboard (EPA)	DTXSID30894055
InChI InChI=1S/Na.HO2/c;1-2/h;1H/q+1;/p-1 Key: TZACNHSIZFFYEH-UHFFFAOYSA-M
SMILES [O-][O].[Na+]
Properties
Chemical formula	NaO₂
Molar mass	54.9886 g/mol
Appearance	Yellow to orange crystalline solid
Density	2.2 g/cm³
Melting point	551.7 °C (1,025.1 °F; 824.9 K)
Boiling point	Decomposes
Solubility in water	Decomposes
Basicity (pK_b)	N/A
Structure
Crystal structure	cubic
Thermochemistry
Heat capacity (C)	72.1 J/mol K
Std molar entropy (S^⦵₂₉₈)	115.9 J/mol K
Std enthalpy of formation (Δ_fH^⦵₂₉₈)	-260.2 kJ/mol
Gibbs free energy (Δ_fG^⦵)	-218.4 kJ/mol
Hazards
GHS labelling:
Pictograms
Signal word	Danger
Hazard statements	H271, H314
Precautionary statements	P210, P220, P260, P280, P303+P361+P353, P305+P351+P338
NFPA 704 (fire diamond)	3 0 1 OX
Flash point	Non flammable
Related compounds
Other anions	sodium oxide sodium peroxide
Other cations	Lithium superoxide Potassium superoxide Rubidium superoxide Caesium superoxide
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). Y verify (what is ^YN ?) Infobox references

Chemical compound

Sodium superoxide is the inorganic compound with the formula NaO₂.^[1] This yellow-orange solid is a salt of the superoxide anion. It is an intermediate in the oxidation of sodium by oxygen.

Preparation

NaO₂ is prepared by treating sodium peroxide with oxygen at high pressures:^[2]

Na₂O₂ + O₂ → 2 NaO₂

It can also be prepared by careful oxygenation of a solution of sodium in ammonia:

Na(in NH₃) + O₂ → NaO₂

It is also produced, along with sodium peroxide, when sodium is stored under inappropriate conditions (e.g. in dirty or partially halogenated solvents)^{[citation needed]}.

Properties

The product is paramagnetic, as expected for a salt of the O⁻
₂ anion. It hydrolyses readily to give a mixture of sodium hydroxide, oxygen and hydrogen peroxide.^[3] It crystallizes in the NaCl motif.

References

^ Hayyan, Maan; Hashim, Mohd Ali; AlNashef, Inas M. (2016-02-15). "Superoxide Ion: Generation and Chemical Implications". Chemical Reviews. 116 (5). American Chemical Society (ACS): 3029–3085. doi:10.1021/acs.chemrev.5b00407. ISSN 0009-2665. PMID 26875845.
^ Stephen E. Stephanou, Edgar J. Seyb Jr., Jacob Kleinberg "Sodium Superoxide" Inorganic Syntheses 1953; Vol. 4, 82-85.
^ Sasol Encyclopaedia of Science and Technology , G.C. Gerrans, P. Hartmann-Petersen , p.243 "sodium oxides" , google books link

Sodium compounds

Inorganic

Halides	NaF NaHF₂ NaCl NaBr NaI NaAt
Chalcogenides	NaO₃ NaO₂ Na₂O Na₂O₂ NaOH NaOD Na₂S NaSH Na₂Se NaSeH Na₂Te NaHTe Na₂Po
Pnictogenides	Na₃N NaN₃ NaNH₂ Na₃P Na₃As
Oxyhalides	NaClO NaClO₂ NaClO₃ NaClO₄ NaBrO NaBrO₂ NaBrO₃ NaBrO₄ NaIO₃ NaIO₄
Oxychalcogenides	Na₂SO₃ Na₂SO₄ NaHSO₃ NaHSO₄ Na₂S₂O₃ Na₂S₂O₄ Na₂S₂O₅ Na₂S₂O₆ Na₂S₂O₇ Na₂S₂O₈ Na₂SeO₃ Na₂SeO₄ NaHSeO₃ Na₂TeO₃
Oxypnictogenides	NaNO₂ NaNO₃ Na₂N₂O₂ NaH₂PO₄ NaPO₂H₂ Na₂HPO₃ Na₂PO₃F Na₃PS₂O₂ Na₃PO₄ Na₅P₃O₁₀ Na₄P₂O₇ Na₂H₂P₂O₇ Na₃AsO₃ Na₃AsO₄ Na₂HAsO₄ NaH₂AsO₄ NaSbO₃
Others	NaAlH₄ NaAlO₂ Na₃AlF₆ NaAl(SO₄)₂ NaAuCl₄ Na₂TiF₆ NaBH₄ NaBH₃(CN) NaBO₂ Na₂B₄O₇ Na₂B₂O₉ Na₂B₈O₁₃ NaBiO₃ NaCN NaCNO NaCoO₂ NaH NaHCO₃ Na₄XeO₆ NaHXeO₄ NaMnO₄ NaOCN NaReO₄ NaSCN NaTcO₃ NaTcO₄ NaVO₃ Na₂CO₃ Na₂C₂O₄ Na₂C₃S₅ Na₂CrO₄ Na₂Cr₂O₇ Na₂Cr₃O₁₀ Na₂GeO₃ Na₂He Na₂[Fe(CO)₄] Na₂MnO₄ Na₂MoO₄ Na₃IrCl₆ Na₂PtCl₆ Na₂O(UO₃)₂ Na₂S₄O₆ Na₂SiO₃ Na₂TiO₃ Na₂U₂O₇ Na₂WO₄ Na₂Zn(OH)₄ Na₃VO₄ Na₆V₁₀O₂₈ Na₄Fe(CN)₆ Na₃Fe(CN)₆ Na₃Fe(C₂O₄)₃ Na₄SiO₄ Na₂SiF₆ Na₃[Co(NO₂)₆] NaNSi₆ Na₂PdCl₄

Organic

CH₃ONa
C₂H₅ONa
HCOONa
C₂H₅COONa
C₃H₇COONa
Na₂C₄H₄O₆
C₄H₅NaO₆
NaCH₃COO
NaC₆H₅CO₂
NaC₆H₄(OH)CO₂
NaC₁₂H₂₃O₂
NaC₁₀H₈
Na₂[Fe[CN₅]NO]
C₆H₁₆AlNaO₄
NaC₆H₇O₆
C₅H₈NO₄Na
C₆H₅Na
C₄H₉Na
NaC₅H₅
C₁₅H₃₁COONa
C₁₇H₃₃COONa
C₁₈H₃₅O₂Na
C₁₆₄H₂₅₆O₆₈S₂Na₂

v t e Oxygen compounds
Ag₄O₄ Al₂O₃ AmO₂ Am₂O₃ As₂O₃ As₂O₅ Au₂O₃ B₂O₃ BaO BeO Bi₂O₃ BiO₂ Bi₂O₅ BrO₂ Br₂O₃ Br₂O₅ Br ₃O ₈ CO CO₂ C₃O₂ CaO CaO₂ CdO CeO₂ Ce₃O₄ Ce₂O₃ ClO₂ Cl₂O Cl₂O₂ Cl₂O₃ Cl₂O₄ Cl₂O₆ Cl₂O₇ CoO Co₂O₃ Co₃O₄ CrO₃ Cr₂O₃ Cr₂O₅ Cr₅O₁₂ CsO₂ Cs₂O₃ CuO Dy₂O₃ Er₂O₃ Eu₂O₃ FeO Fe₂O₃ Fe₃O₄ Ga₂O Ga₂O₃ GeO GeO₂ H₂O ²H₂O ³H₂O H₂¹⁸O H₂O₂ HfO₂ HgO Hg₂O Ho₂O₃ IO I₂O₄ I₂O₅ I₂O₆ I₄O₉ In₂O₃ IrO₂ KO₂ K₂O₂ La₂O₃ Li₂O Li₂O₂ Lu₂O₃ MgO Mg₂O₃ MnO MnO₂ Mn₂O₃ Mn₂O₇ MoO₂ MoO₃ Mo₂O₃ NO NO₂ N₂O N₂O₃ N₂O₄ N₂O₅ NaO₂ Na₂O Na₂O₂ NbO NbO₂ Nd₂O₃ O₂F OF OF₂ O₂F₂ O₃F₂ O₄F₂ O₅F₂ O₆F₂ O₂PtF₆ more...