## How to Find the Roman Numeral

Frederick Keith_4C
Posts: 65
Joined: Thu Sep 26, 2019 12:19 am

### How to Find the Roman Numeral

I already asked what the roman numeral represents, but this time I'm asking how do you find it?
For example, if the compound was [Co (NH)3 (H2O)3]2 (SO4^-2)3 what would the name and roman numeral be?

DarrenKim_1H
Posts: 123
Joined: Fri Sep 20, 2019 12:17 am
Been upvoted: 1 time

### Re: How to Find the Roman Numeral

So that coordination compound is shown to be neutral. So you would find the net negative charge of 3 So4^2-, which is -6 (3 times -2). In the cation, NH3 and H2O are both neutral so Cobalt is the only component that has a charge which is +3.
Overall, its a net positive charge of +6 since (2 times 3 = 6).

Therefore, the whole compound is neutral. (6-6 = 0 charge)

Matt F
Posts: 100
Joined: Sat Aug 17, 2019 12:17 am

### Re: How to Find the Roman Numeral

Typically you want to find it by process of elimination. See what the overall charge of the coordination compound is, and then determine what components inside are that make it up. From there, the roman numeral will take on whatever value it needs to be so that the components equal the total charge. Hope this helps!

Posts: 50
Joined: Wed Sep 11, 2019 12:17 am

### Re: How to Find the Roman Numeral

so is it usually the charge found for the transition metal

Amy Kumar 1I
Posts: 114
Joined: Thu Jul 11, 2019 12:15 am

### Re: How to Find the Roman Numeral

Work backwards from the overall charge and charge of the ligands to find the charge on the metal.