Dubnium - wikipedia, Dubnium chemical element symbol db atomic number 105. transactinide element, dubnium highly radioactive: stable isotope, dubnium-268. https://en.wikipedia.org/wiki/Dubnium Table common polyatomic ions - department chemistry, The tables list common polyatomic ions general-chemistry laboratory series (chem 151-152). ions separated . http://www.chemistry.wustl.edu/~edudev/LabTutorials/PeriodicProperties/Ions/ions.html Common polyatomic ions, Title: common polyatomic ions author: jeremy schneider created date: 10/22/2007 8:52:09 pm. http://www.chalkbored.com/lessons/common-polyatomic-ions.pdf