Question

I need help whith Identifiying the name of the compound Cr2(CO3)3? step by step please?

Answer 1

If you look on the periodic table, Cr stands for Chromium.
CO3 is the compound Carbonate. You know that C is Carbon. The ending "ate" is used when the subscript of Oxygen is the highest it can be for the compound. In this case, CO3 is the highest (not CO4) so it ends in "ate".

Since CO3 has a charge of -2, and there are 3 of them, you know that the charge for (CO3)3 is -6. That means that Cr2 must also have a charge of -6 for it to balance out. Knowing that, you take -6 divided by 2 molecules of Cr, you get that Cr has a charge of -3. This is important because Cr can either be -2 or -3.

Therefore, your answer would be Chromium III Carbonate.

Answer 2

Take note of the mistakes above:
That means that Cr2 must also have a charge of +6 for it to balance out. Knowing that, you take +6 divided by 2 molecules of Cr, you get that Cr has a charge of +3. This is important because Cr can either be +2 or +3.

Changed the charges - chromium is a metal and can only for cations :)
anemonix explained it well

Answer 3

^ Whoops, yep, Cr's charges should be positive to balance out that of Carbonate. Sorry for the typo ><

Answer 4

O.o!!!! thanks hehe