Does the recent certificate gotofail bug affect me if I'm running version 6 of iOS, but only use Chrome as my browser?
No, Chrome on iOS is not affected by this bug as it doesn't use Apple's offical SSL/TLS library.
On Mac OS X, Chrome and Mozilla Firefox are not affected either.
Note that other applications than internet browsers are affected by this bug, in fact any application that relies on Apple's SSL/TLS library to encrypt data is affected (e.g. Mail, Calendar, etc.).