I need to name an ionic compound containing a transition metal cation and a halogen anion. Below are the rules I should follow to write the correct name for such compound, but one of the options is incorrect: identify and select it. a. Identify the metal and write its name first
b. Use the periodic table to work out the charge (oxidation number) on the transition metal according to the group in the periodic table
c. From the charge of the anion work out the charge of cation as Roman number in parenthesis: specify this charge in the name as a Roman number in parenthesis.
d. Write the number of the anion after the name of the metal

The iconic compounds obtain a transition of metal caution and a halon anon. As per the rules the correct name of the compounds should be written as to identify the incorrect one.

Learn more about the ionic compound containing a transition metal.

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b. Use the periodic table to work out the charge (oxidation number) on the transition metal according to the group in the periodic table

Explanation:

The keyword in this problem us "transition metal". Transition metals are found between the group 2 and group 3 elements. They have the d sub shells and also exhibit variable oxidation numbers (valency).

Among the options, the incorrect option is option B.

This is because transition metals d not have  a fixed oxidation number and they cannot be obtained by looking up the group in the periodic table.

it is the most commonly accepted one