Answer
nickel (II) oxide
$2^+$
Work Step by Step
$NiO$
$Ni$ is nickel.
$O$ is oxygen, which his called oxide when naming compounds.
Oxygen has a charge of -2. The compound is neutral, so the charge/oxidation number of the nickel element was +2.
The name is written as element(oxidation number) element so
$NiO$ is nickel (II) oxide.
