How to Determine the Charge of Transition Metals

The charge of transition metals varies depending on the nature of the elements with which they combine.

Most elements are predictable in their ion-forming interactions with other elements. A notable exception is the set of 38 elements that lie between groups III and XII of the periodic table. In these elements called transition metals, the valence electrons exist in different shells. Therefore, these metals are capable of combining with non-metal elements in different ways, to form more than one ion. Depending on the compound they form, the transition metals exist in a particular oxidation state that decides the charge they carry.

Instructions

1. Study the compound that a given transition metal forms by combination with another element. Note the name of the compound and its net charge.

2. Use the guidelines that describe the possible oxidation states of nonmetal elements to determine the charge of the transition metal. For example, as per these guidelines, when oxygen interacts with a metal, it always exists as an ion with a (-2) charge. In the compound manganese dioxide (MnO2), there are two oxygen ions with a total charge of (-4), but the MnO2 species bears no net charge. This indicates that the charge on the manganese ion is (+4).

3. Find out the different compounds that result from a combination of a transition metal with a nonmetal. For example, when copper reacts with chlorine, it may form cuprous chloride (CuCl) or cupric chloride (CuCl2). Apply the guidelines for chlorine which state that it reacts with metals and always bears a charge of (-1). Cuprous chloride has a single chloride ion and therefore, the charge on copper here is (+1). Cupric chloride has two chloride ions with a charge of (-2); because cupric chloride bears no net charge, the charge on the copper ion here must be (+2).

4. Check the solubility of the compound formed by combination of the transition metal with the nonmetal. If this compound is soluble in water, it indicates that the charge on the transition metal ion is smaller than (+3) because a charge greater than (+3) causes precipitation of the transition metal ion.

References

• Bellevue College, Science Division: Charges
• Purdue University, College of Science: Transition Metals
• Kapi'olani Community College Library: Oxidation States of Transition Metals
• Chemical Elements.com: Transition Metals