WHAT TYPE OF REACTION IS HAPPENING WITH NI2O3 (s) Ni (s) + O2 (g)

Decomposition.

Explanation:

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In this case, since we can find four types of reactions, combination, decomposition, single displacement and double displacement, for the reaction:

2NI2O3 (s) --> 4Ni (s) + 3O2 (g)

We can evidence that the reactant (only one) is separated into the elements forming it; therefore, we infer this is a decomposition reaction.

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