In Mendeleev's 1871 periodic table, copper, silver, and gold are detailed two times, the moment under group VIII (While using the iron triad and platinum group metals), and after beneath group IB. Group IB was Nevertheless parenthesised to notice that it was tentative. Mendeleev's primary criterion for group assignment was https://jeffreykkhcx.webbuzzfeed.com/36358194/the-best-side-of-bigbos777-situs-slot