Group 12 elements have partially filled (n − 1)d subshells, and hence are not, strictly speaking, transition metals. Nonetheless, much of their chemistry is similar to that of the elements that immediately precede them in the d block. The group 12 metals are similar in abundance to those of group 11, and they are almost always found in combination with sulfur. Group 12 metals tend have low melting and boiling points (due to the weak metallic bonding of the ns 2 electrons) and charges of +2 or +1.