TQ53

KM> (the value of
       (the output of 
	    (a Compute-Oxidation-State with
	       (input ((a NO3-Minus))))))
((:pair -2 O) (:pair 5 N))

KM> (justify (:triple (thelast Compute-Oxidation-State) output *))

For monatomic ions the oxidation number is the charge on the ion.
Therefore, the oxidation number of NO3- is -1.
Finding rules for computing the oxidation numbers for the atoms in NO3-.
No rules found.

Since no rules were found for O and one other atom, the oxidation
state of O is -2. The oxidation state O(x) of N in NO3- can be
computed from the formula O(x) = C - (Z(x) / S(x)), where C is the
compound charge, S(x) is the subscript of atom x and Z(x) is the sum
of the products of the other atoms in the compound and their
subscripts.

The oxidation state of N in NO3- is thus -1 - (-6 / 1) = 5.

The oxidation state O(x) of N O in NO3- can be computed from the
formula O(x) = C - (Z(x) / S(x)), where C is the compound charge, S(x)
is the subscript of atom x and Z(x) is the sum of the products of the
other atoms in the compound and their subscripts.

The oxidation state of O in NO3- is thus -1 - (3 / 3) = -2 N in NO3-
is thus -1 - (-6 / 1) = 5.