Chemistry informtion about 2-Nitrophenylhydrazine (CAS NO.3034-19-3) is:
IUPAC Name: (2-Nitrophenyl)Hydrazine
Synonyms: (O-Nitrophenyl)-Hydrazin ; O-Nitrophenythydrazine ; O-Nitrophenylhydrazine ; 1-(2-Nitrophenyl)Hydrazine ; 2-Nitrophenylhydrazine ; 2-Nitrophenylhydrazine, Moistened With Ca 30% Water, 97% ; 2-Nitrophenylhydrazine (Base And/Or Unspecified Salts) ; 2-Nitrophenylhydrazine 98+%
Product Categories: Aromatic Hydrazides, Hydrazines, Hydrazones and Oximes ; Hydrazines ; Nitrogen Compounds ; Organic Building Blocks 
MF: C₆H₇N₃O₂
MW: 153.14
EINECS: 221-222-6 
Density: 1.419 g/cm³ 
Melting Point: 91-93 °C(lit.)
Flash Point: 143.9 °C
Boiling Point: 314.3 °C at 760 mmHg
Vapour Pressure: 0.000469 mmHg at 25°C 
Enthalpy of Vaporization: 55.55 kJ/mol
Storage temp.:  2-8°C
Sensitive: Light Sensitive
BRN: 512797 
Following is the molecular structure of 2-Nitrophenylhydrazine (CAS NO.3034-19-3) is:

Poison by intravenous route. Mutation data reported. When heated to decomposition it emits toxic fumes of NO_x. See also NITRO COMPOUNDS of AROMATIC HYDROCARBONS.
Hazard Codes:
Xi
Risk Statements:
R36/37/38:Irritating to eyes, respiratory system and skin.
Safety Statements:
S26: In case of contact with eyes, rinse immediately with plenty of water and seek medical advice. 
S36:Wear suitable protective clothing.
RIDADR: UN 1325 4.1/PG 2
WGK Germany: -
RTECS: MV8210000
F:
F 4.6: Do not heat over 60°C. 
F 8: Photosensitive.
HazardClass: 4.1
PackingGroup: III

2-Nitrophenylhydrazine (CAS NO.3034-19-3) is a orange to orange-brown powder.
First Aid Measures:
Eyes: Flush eyes with plenty of water for at least 15 minutes, occasionally lifting the upper and lower eyelids. Get medical aid.
Skin: Get medical aid. Flush skin with plenty of water for at least 15 minutes while removing contaminated clothing and shoes.
Ingestion: Get medical aid. Wash mouth out with water.
Inhalation: Remove from exposure and move to fresh air immediately. If not breathing, give artificial respiration. If breathing is difficult, give oxygen. Get medical aid.
Notes to Physician: Treat symptomatically and supportively. 
Handling and Storage
Handling: Use spark-proof tools and explosion proof equipment. Avoid breathing dust, vapor, mist, or gas. Avoid contact with skin and eyes. Avoid ingestion and inhalation.
Storage: Keep away from sources of ignition. Store in a tightly closed container. Store in a dry area. Flammables-area. Keep refrigerated. (Store below 4°C/39°F.) Store protected from light.