Mercury(II) oxide
| Names | |
|---|---|
| IUPAC name Mercury(II) oxide | |
| Other names | |
| Identifiers | |
| 3D model (JSmol) | |
| ChemSpider | |
| ECHA InfoCard | 100.040.580 | 
| KEGG | |
| PubChem CID | |
| RTECS number | 
 | 
| UNII | |
| UN number | 1641 | 
| CompTox Dashboard (EPA) | |
| 
 | |
| 
 | |
| Properties | |
| HgO | |
| Molar mass | 216.591 g·mol−1 | 
| Appearance | Yellow or red solid | 
| Odor | odorless | 
| Density | 11.14 g/cm3 | 
| Melting point | 500 °C (932 °F; 773 K) (decomposes) | 
| 0.0053 g/100 mL (25 °C) 0.0395 g/100 mL (100 °C) | |
| Solubility | insoluble in alcohol, ether, acetone, ammonia | 
| Band gap | 2.2 eV | 
| −44.0·10−6 cm3/mol | |
| Refractive index (nD) | 2.5 (550 nm) | 
| Thermochemistry | |
| Std molar entropy (S⦵298) | 70 J·mol−1·K−1 | 
| Std enthalpy of formation (ΔfH⦵298) | −90 kJ·mol−1 | 
| Hazards | |
| Occupational safety and health (OHS/OSH): | |
| Main hazards | Extremely toxic, environmental pollutant | 
| GHS labelling: | |
| Danger | |
| H300+H310+H330, H372, H410 | |
| P260, P262, P264, P270, P271, P273, P280, P284, P301+P316, P302+P352, P304+P340, P316, P320, P321, P330, P361+P364, P391, P403+P233, P405, P501 | |
| NFPA 704 (fire diamond) | |
| Flash point | Non-flammable | 
| Lethal dose or concentration (LD, LC): | |
| LD50 (median dose) | 18 mg/kg (oral, rat) | 
| Safety data sheet (SDS) | ICSC 0981 | 
| Related compounds | |
| Other anions | Mercury sulfide Mercury selenide Mercury telluride | 
| Other cations | Zinc oxide Cadmium oxide | 
| Related compounds | Mercury(I) oxide | 
| Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). Infobox references | |
Mercury(II) oxide, also called mercuric oxide or simply mercury oxide, is the inorganic compound with the formula HgO. It has a red or orange color. Mercury(II) oxide is a solid at room temperature and pressure. The mineral form montroydite is very rarely found.