Product Identification
【Product Name】4-Hydrazinobenzenesulfonic acid
【Synonyms】p-Sulfophenylhydrazine ；4-肼基苯磺酸
【CAS】98-71-5
【Formula】C6H8N2O3S
【Molecular Weight】188.21
【EINECS】202-694-2
【RTECS】DB6900000
【RTECS Class】Other
【Merck】13,4793
【Beilstein/Gmelin】514779
【Beilstein Reference】3-15-00-00865

Physical and Chemical Properties
【Appearance】White to off-white solid.
【Solubility in water】Very soluble
【Melting Point】285℃
【Boiling Point】373℃
【pKa/pKb】9.15 (pKb)
【Partition Coefficient】.2

First Aid Measures
【Ingestion】Never give anything by mouth to an unconscious person. Get medical aid. Do NOT induce vomiting. If conscious and alert, rinse mouth and drink 2-4 cupfuls of milk or water.
【Inhalation】Remove from exposure to fresh air immediately. If not breathing, give artificial respiration. If breathing is difficult, give oxygen. Get medical aid.
【Skin】Get medical aid. Flush skin with plenty of soap and water for at least 15 minutes while removing contaminated clothing and shoes. Wash clothing before reuse.
【Eyes】Flush eyes with plenty of water for at least 15 minutes, occasionally lifting the upper and lower eyelids. Get medical aid.

Handling and Storage
【Storage】Store in a tightly closed container. Store in a cool, dry, well-ventilated area away from incompatible substances.
【Handling】Wash thoroughly after handling. Remove contaminated clothing and wash before reuse. Use with adequate ventilation. Minimize dust generation and accumulation. Avoid contact with eyes, skin, and clothing. Keep container tightly closed. Avoid ingestion and inhalation.

Hazards Identification
【Ingestion】May cause irritation of the digestive tract. The toxicological properties of this substance have not been fully investigated.
【Inhalation】May cause respiratory tract irritation. The toxicological properties of this substance have not been fully investigated.
【Skin】May cause skin irritation. The toxicological properties of this material have not been fully investigated.
【Eyes】May cause eye irritation. The toxicological properties of this material have not been fully investigated.
【EC Risk Phrase】R 22 34
【EC Safety Phrase】S 26 36/37/39 45
【UN (DOT)】3265

Exposure Controls/Personal Protection
【Personal Protection】Eyes: Wear appropriate protective eyeglasses or chemical safety ggles as described by OSHA's eye and face protection regulations in 29 CFR 1910.133 or European Standard EN166. Skin: Wear appropriate protective gloves to prevent skin exposure. Clothing: Wear appropriate protective clothing to prevent skin exposure.
【Respirators】Follow the OSHA respirator regulations found in 29CFR 1910.134 or European Standard EN 149. Always use a NIOSH or European Standard EN 149 approved respirator when necessary.

Fire Fighting Measures
【Fire Fighting】Wear a self-contained breathing apparatus in pressure-demand, MSHA/NIOSH (approved or equivalent), and full protective gear. During a fire, irritating and highly toxic gases may be generated by thermal decomposition or combustion. Extinguishing media: Use agent most appropriate to extinguish fire. In case of fire use water spray, dry chemical, carbon dioxide, or appropriate foam.

Accidental Release Measures
【Small spills/leaks】Vacuum or sweep up material and place into a suitable disposal container. Clean up spills immediately, using the appropriate protective equipment. Avoid generating dusty conditions. Provide ventilation.

Stability and Reactivity
【Incompatibilities】Oxidizing agents.
【Stability】Stable under normal temperatures and pressures.
【Decomposition】Carbon monoxide, oxides of nitrogen, oxides of sulfur, irritating and toxic fumes and gases, carbon dioxide.

Transport Information
【UN Number】3265