Naming -ate

[Michelle Dong 1F]

I know that we add "-ate" to the end of a metal name if the complex has a negative charge (eg: [Ni(CN)4]2- is ...nickelate (II)), but why is it that in some cases, we still use "-ate" even though the complex does not have an overall negative charge? An example would be K3[CoF6], which is named Potassium hexa-fluorido cobaltate (III).

[Ryan Sydney Beyer 2B]

Sometimes we use the "ate" suffix to differentiate between whether it is a cation or an anion. In this specific situation, the coordination sphere has an overall negative charge and therefore we should be indicating that this is an anion.

[Jessica Yang 1J]

The complex, which doesn't include the potassium is still negative. The 6 F's create a -6 charge and the Co creates a +3 charge, resulting in an overall -3 charge for the complex. The entire coordination compound, which includes the potassium, is of neutral charge.