Chapter 9, Problem 4STP

Interpretation Introduction

Interpretation: The meaning of the Roman numeral in the given name is to be stated.

Concept Introduction: An ionic compound is named by writing the name of the metal followed by its oxidation state/ charge in Roman numerals in parenthesis. Then, the name of the non-metal is written with an ending ‘−ide’.

Answer to Problem 4STP

The Roman numeral in manganese (IV) sulfide indicates the positive charge on the manganese ion. Hence option (B) is the correct answer.

Explanation of Solution

In the IUPAC naming system, the charge on the metal ion is written in parenthesis in Roman numerals after the name of the metal. So (IV) indicates the charge on the manganese atom.

Hence, the correct option is (B).

Conclusion

For other options, the group number is indicated by the valency of an atom. The number of Mn ions is represented by its subscript in the chemical formula. The number of sulfide ions needed in the formula is calculated by the charge on the Mn metal.

Hence, the incorrect options are (A), (C), and (D).