Zinc Oxide

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Zinc Oxide (Wikipedia)
Zinc oxide
Zinc oxide.jpg
Names
Other names
Zinc white, calamine, philosopher's wool, Chinese white, flowers of zinc
Identifiers
1314-13-2 YesY
ChEBI CHEBI:36560 YesY
ChEMBL ChEMBL1201128 N
ChemSpider 14122 YesY
EC Number 215-222-5
PubChem 14806
RTECS number ZH4810000
Properties
ZnO
Molar mass 81.38 g/mol
Appearance White solid
Odor odorless
Density 5.606 g/cm3
Melting point 1,975 °C (3,587 °F; 2,248 K) (decomposes)
Boiling point 1,975 °C (3,587 °F; 2,248 K) (decomposes)
0.0004% (17.8°C)
Band gap 3.3 eV (direct)
2.0041
Structure
Wurtzite
C6v4-P63mc
a = 3.25 Å, c = 5.2 Å
Tetrahedral
Thermochemistry
43.9 J·K−1mol−1
-348.0 kJ/mol
Pharmacology
QA07XA91 (WHO)
Hazards
Safety data sheet ICSC 0208
Dangerous for the environment (N)
R-phrases R50/53
S-phrases S60, S61
NFPA 704
Flammability code 1: Must be pre-heated before ignition can occur. Flash point over 93 °C (200 °F). E.g., canola oilHealth code 2: Intense or continued but not chronic exposure could cause temporary incapacitation or possible residual injury. E.g., chloroformReactivity code 0: Normally stable, even under fire exposure conditions, and is not reactive with water. E.g., liquid nitrogenSpecial hazard W: Reacts with water in an unusual or dangerous manner. E.g., cesium, sodiumNFPA 704 four-colored diamond
Flash point 1,436 °C (2,617 °F; 1,709 K)
Lethal dose or concentration (LD, LC):
240 mg/kg (intraperitoneal, rat)
7950 mg/kg (rat, oral)
2500 mg/m3 (mouse)
2500 mg/m3 (guinea pig, 3–4 hr)
US health exposure limits (NIOSH):
PEL (Permissible)
TWA 5 mg/m3 (fume) TWA 15 mg/m3 (total dust) TWA 5 mg/m3 (resp dust)
REL (Recommended)
Dust: TWA 5 mg/m3 C 15 mg/m3

Fume: TWA 5 mg/m3 ST 10 mg/m3

IDLH (Immediate danger)
500 mg/m3
Related compounds
Other anions
Zinc sulfide
Zinc selenide
Zinc telluride
Other cations
Cadmium oxide
Mercury(II) oxide
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
N verify (what is YesYN ?)
Infobox references

Zinc oxide is an inorganic compound with the formula ZnO. ZnO is a white powder that is insoluble in water, and it is widely used as an additive in numerous materials and products including rubbers, plastics, ceramics, glass, cement, lubricants, paints, ointments, adhesives, sealants, pigments, foods, batteries, ferrites, fire retardants, and first-aid tapes. It occurs naturally as the mineral zincite, but most zinc oxide is produced synthetically.

ZnO is a wide-bandgap semiconductor of the II-VI semiconductor group. The native doping of the semiconductor due to oxygen vacancies or zinc interstitials is n-type. This semiconductor has several favorable properties, including good transparency, high electron mobility, wide bandgap, and strong room-temperature luminescence. Those properties are valuable in emerging applications for: transparent electrodes in liquid crystal displays, energy-saving or heat-protecting windows, and electronics as thin-film transistors and light-emitting diodes.

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