Question

question 15 of 25
how is the oxidation state of a transition metal determined from the chemical formula?
a. a roman numeral placed after the transition metal identifies its oxidation state.
b. the subscript of the negative ion identifies the oxidation state of the transition metal.
c. the subscript of the transition metal in the formula identifies its oxidation state.
d. a superscript on the transition metal identifies its oxidation state in the formula.

Explanation:

In naming compounds with transition - metals, a Roman numeral placed after the transition metal in the name (derived from the chemical formula) indicates its oxidation state. For example, in iron(III) oxide ($Fe_2O_3$), the (III) indicates the + 3 oxidation state of iron. The subscript of an ion does not directly identify the oxidation state of the transition metal, and there are no superscripts on the transition metal in the standard chemical formula that identify its oxidation state in the way described in options B, C, and D.

Answer:

A. A Roman numeral placed after the transition metal identifies its oxidation state.