Here's why:

* Ionic Compounds: Nickel bromide is an ionic compound, meaning it is formed by the electrostatic attraction between positively charged nickel ions (Ni²⁺) and negatively charged bromide ions (Br⁻).

* Polarity: Water is a polar solvent, meaning it has a positive and negative end due to the uneven sharing of electrons. This allows water molecules to surround and interact with the charged ions of nickel bromide, breaking the ionic bonds and dissolving the compound.

While nickel bromide is soluble in water, it's important to note that its solubility is limited. It's not as soluble as something like sodium chloride (table salt), but it's still considered soluble.