Chemical Forums

Chemistry Forums for Students => Undergraduate General Chemistry Forum => Topic started by: maccha on November 07, 2009, 01:46:26 PM

Title: Formal charge question
Post by: maccha on November 07, 2009, 01:46:26 PM

Do complex ions form because of formal charges? For instance, in the hydroxide ion the oxygen has a negative formal charge.. is this what creates the overall negatively charged ion?

Title: Re: Formal charge question
Post by: aurophilic on November 07, 2009, 04:19:36 PM

Yes, that sounds right.

Title: Re: Formal charge question
Post by: cth on November 08, 2009, 07:24:46 AM

Partially yes. A negative charge on the ligand will help to bind to a positively charged metallic cation.

But some ligands are not actually charged, for example NH₃, CO, PPh₃, pyridine,... It is the lone electrons on the ligands that become shared with the metal cation when the complex form.