IUPAC:  Mercury(2+) sulfate
 Mercury(II) sulfate (1:1) (7783-35-9)  is also called for  EINECS 231-992-5 ; HSDB 1247 ; Mercuric bisulphate ; Mercuric sulfate ; Mercury bisulfate ; Mercury disulfate ; Mercury persulfate ; Mercury sulfate (HgSO4) ; Sulfate mercurique ; Sulfuric acid, mercury(2+) salt (1:1) ; Mercury sulphate and so on.
Molecular Formula: HgO₄S
Molecular Weight: 296.65
EINECS: 231-992-5
LogP: ACD/LogP: -1.03
ACD/LogD (pH 5.5): -5.53 
ACD/LogD (pH 7.4): -5.53 
ACD/BCF (pH 5.5): 1 
ACD/BCF (pH 7.4): 1 
ACD/KOC (pH 5.5): 
ACD/KOC (pH 7.4): 
H bond acceptors: 4 
H bond donors: 2 
Freely Rotating Bonds: 0
Heavy Atom Count: 6
Formal Charge: 0
Complexity: 62.2
Isotope Atom Count: 0
Defined Atom StereoCenter Count: 0
Undefined Atom StereoCenter Count: 0
Defined Bond StereoCenter Count: 0
Undefined Bond StereoCenter Count: 0
Covalently-Bonded Unit Count: 2 
Enthalpy of Vaporization: 62.94 kJ/mol 
Boiling Point: 330°C at 760 mmHg 
Vapour Pressure: 3.35E-05 mmHg at 25°C 
The appearance of   Mercury(II) sulfate (1:1) (7783-35-9)  is white crystal powder.
The molecular structure of   Mercury(II) sulfate (1:1) (7783-35-9) :

Mercury and its compounds are on the Community Right-To-Know List. Reported in EPA TSCA Inventory.

Poison by ingestion and intraperitoneal routes. Moderately toxic by skin contact. When heated to decomposition it emits very toxic fumes of Hg and SO_x. See also MERCURY COMPOUNDS, INORGANIC; MERCURY COMPOUNDS, ORGANIC.

Hazard Codes:  T+,T , N
Risk Statements: 26/27/28-33-50/53-51/53-42/43-36/38-61-60-46-45-52/53-35-23/24/25
R26/27/28: Very Toxic by inhalation, in contact with skin and if swallowed
R33: Danger of cumulative effects
R50/53: Very Toxic to aquatic organisms, may cause long-term adverse effects in the aquatic environment
R51/53: Toxic to aquatic organisms, may cause long-term adverse effects in the aquatic environment
R42/43: May cause sensitization by inhalation and skin contact
R36/38: Irritating to eyes and skin
R61: May cause harm to the unborn child
R60: May impair fertility
R46: May cause heritable genetic damage
R45: May cause cancer
R52/53: Harmful to aquatic organisms, may cause long-term adverse effects in the aquatic environment
R35: Causes severe burns
R23/24/25: Toxic by inhalation, in contact with skin and if swallowed
Safety Statements:  13-28-45-60-61-36/37-26-23-53-36/37/39-30
S13: Keep away from food, drink and animal feeding stuffs
S28: After contact with skin, wash immediately with plenty of ... (to be specified by the manufacturer)
S45: In case of accident or if you feel unwell, seek medical advice immediately (show label where possible)
S60: This material and/or its container must be disposed of as hazardous waste
S61: Avoid release to the environment. Refer to special instructions safety data sheet
S36/37: Wear suitable protective clothing and gloves
S26: In case of contact with eyes, rinse immediately with plenty of water and seek medical advice
S23: Do not breathe gas/fumes/vapor/spray (appropriate wording to be specified by the manufacturer)
S53: Avoid exposure - obtain special instruction before use
S36/37/39: Wear suitable protective clothing, gloves and eye/face protection
S30: Never add water to this product
RIDADR:  UN 1645 6.1/PG 2
WGK Germany:  3
RTECS:  OX0500000
HazardClass:  6.1
PackingGroup:  II

OSHA PEL: CL 0.1 mg(Hg)/m³ (skin)
ACGIH TLV: TWA 0.1 mg(Hg)/m³ (skin); BEI: 35 µg/g creatinine total inorganic mercury in urine preshift; 15 µg/g creatinine total inorganic mercury in blood at end of shift at end of workweek.
NIOSH REL: (Mercury, Aryl and Inorganic) CL 0.1 mg/m³ (skin)

1.Handling and Storage
Handling: Do not breathe dust, vapor, mist, or gas. Do not get in eyes, on skin, or on clothing. Do not ingest or inhale. Use only in a chemical fume hood. 
Storage: Store in a cool, dry place. Store in a tightly closed container. Poison room locked. Store under an inert atmosphere. 
2.Fire Fighting Measures 
General Information: As in any fire, wear a self-contained breathing apparatus in pressure-demand, MSHA/NIOSH (approved or equivalent), and full protective gear. 
Extinguishing Media: Use water spray, dry chemical, carbon dioxide, or chemical foam.