Question

How would you name the ion?

Answer 1

cromate ion

Answer 2

How did you find it?

Answer 3

Chromate ion is \(CrO_4^{2-}\)

Answer 4

Try typing Cr2O7 in Wikipedia

Answer 5

But that's cheating and you can't do it on a test D:

Answer 6

Then you have to be familiar with the most common ions and have an idea of the way others are named.

For instance, all monatomic anions have the name of the element with an -ide ending.