Nickel nitrate (Ni(NO₃)₂) is a green crystalline solid, commonly hexahydrate (Ni(NO₃)₂·6H₂O), soluble in water and ethanol. Prepared via nickel oxide reacting with nitric acid or nickel carbonyl with N₂O₄ , it serves as a precursor for nickel catalysts in electroplating, ceramics, and battery production . Classified as a Group 1 carcinogen , it acts as a strong oxidizer, posing fire/explosion risks when heated with combustibles . Requires PPE, ventilation, and strict handling due to nickel toxicity