The production of elements in supernova explosions is something we take for granted these days. But exactly where and when this nucleosynthesis takes place is still unclear – and attempts to computer model core collapse scenarios still pushes current computing power to its limits.
Stellar fusion in main sequence stars can build some elements up to, and including, iron. Further production of heavier elements can also take place by certain seed elements capturing neutrons to form isotopes. Those captured neutrons may then undergo beta decay leaving behind one or more protons which essentially means you have a new element with a higher atomic number (number of protons in the atomic nucleus).
This ‘slow’ process or s-process of building heavier elements from, say, iron (26 protons) takes place most commonly in red giants (making elements like copper with 29 protons and even thallium with 81 protons).
But there’s also the rapid or r-process, which takes place in a matter of seconds in core collapse supernovae (being supernova types 1b, 1c and 2). Rather than the steady, step-wise building over thousands of years seen in the s-process – seed elements in a supernova explosion have multiple neutrons jammed in to them, while at the same time being exposed to disintegrating gamma rays. This combination of forces can build a wide range of light and heavy elements, notably very heavy elements from lead (82 protons) up to plutonium (94 protons), which cannot be produced by the s-process.
Arcones A. and Janka H. Nucleosynthesis-relevant conditions in neutrino-driven supernova outflows. II. The reverse shock in two-dimensional simulations.
And, for historical context, the seminal paper on the subject (also known as the B2FH paper) E. M. Burbidge, G. R. Burbidge, W. A. Fowler, and F. Hoyle. (1957). Synthesis of the Elements in Stars. Rev Mod Phy 29 (4): 547.
Science Units that use PowerPoint presentations in a refreshing new way to present class notes, labs, assessments, project ideas, discussion questions and much more for educators and homeschool parents for grades 5-10.
This main page provides downloadable PowerPoint presentations on teh atom and the Periodic Table. This also provides some quizzing. Very useful for both classroom and individual learning.
Interactive Periodic Table site that begins with a review of the basics of the atom and then tests your learning with a quiz on understanding ions vs atoms and naming elements based on atomic information.
The 80's band They Might Be Giants have moved to teaching young people about a number of topics. In this song, they related how elements combine to create molecules. Not specifically on the Periodic Table, but great fun.