Compounds. There are more carbon compounds than there are compounds of all other elements combined. The study of carbon compounds, both natural and synthetic, is called organic chemistry. Plastics, foods, textiles, and many other common substances contain carbon.
backplane is the shared capacity between interfaces on a switch switch fabric is also the shared capacity between interfaces on a switch and can also be the shared capacity between interfaces on multiple switches using some sort of interconnect, typically vendor specific.
Therefore, if the ingress and egress ports are both on the same stack member (i.e. same switch), then the stack ring isn't used at all. Backplane bandwidth for connecting the 48 ports (and network module, if fitted) is sufficient to enable non-blocking. However, 48 ports x 1Gbps (plus potentially 2 x 10Gbps in network module) definitely doesn't squeeze into 32Gbps stack ring, so the stack ring is contended.