The “lead” of a pencil is actually made of a substance called graphite which is made of carbon atoms. The picture shows a close-up of one carbon atom. A hydrogen atom has one proton as the nucleus and ...

Carbon-12 makes up 99% of an atom, carbon-13 makes up 1% and carbon ... Radioactive atoms decay into stable atoms by a simple mathematical process. Half of the available atoms will change in ...

In these drawings, every line is a bond and every bend is a carbon atom. Most hydrogen atoms are not shown, and it is assumed each carbon has enough hydrogens so that each carbon has four bonds.