Nickel does not react with water at room temperature. However, at high temperatures, nickel can react with water to form nickel oxide (NiO) and hydrogen gas (H2). The reaction is as follows:

Ni(s) + H2O(g) → NiO(s) + H2(g)

The reaction is reversible and the equilibrium constant is dependent on temperature. At low temperatures, the equilibrium constant is small and the reaction does not proceed to a significant extent. However, as the temperature increases, the equilibrium constant increases and the reaction proceeds to a greater extent.