Analysis shows that nickel oxide has the formula `Ni_(0.98)O_(1.00)`. What fractions of nickel "exist" as `Ni^(2+)` and `Ni^(3+)` ions?

Explanation

`Ni_(0.98)O_(1.0)`
Let `Ni^(2+)` be x so that `Ni^(3+)` will be `0.98 - x`. Total charge on the compound must be zero so that
`+2x + 3(0.98 - x) - 2 = 0`
`2x + 2.94 - 3x - 2 = 0`
`-x = -0.94`
or `x = 0.94`
`% " of " Ni^(2+) = (0.94)/(0.98) xx 100 = 96%`
`% " of " Ni^(3+) = 4%`.