NiBr3=

NiBr3 likely means nickel(III) bromide.

• Oxidation state: Bromide is -1 each, so three Br− give -3; Ni must be +3 to balance. So Ni is in the +3 oxidation state (nickel(III)).
• Stability: Ni(III) compounds are uncommon and NiBr3 is not very stable in water/air; it’s typically prepared and studied in dry, non-aqueous conditions (often as a coordination/polymeric solid or complex).
• If you were asking about a reaction: NiBr2 can be oxidized by Br2 (or another oxidant) to form NiBr3 in a suitable solvent, but details depend on the exact conditions.

If you meant something different (e.g., you want a balanced equation, structure, or synthesis), tell me the context and I’ll tailor it.