Never-before-seen “black nitrogen” plugs puzzle in periodic table
What are some other open mysteries in physics / chemistry / science? Anyone have some favorites?<p>Bonus points for simplicity + obscurity. Everyone knows that dark matter is an open mystery, but I suspect not too many people knew about black nitrogen.<p>EDIT: There are some nice lists on Wikipedia that are fun to dig through: <a href="https://en.wikipedia.org/wiki/Lists_of_unsolved_problems" rel="nofollow">https://en.wikipedia.org/wiki/Lists_of_unsolved_problems</a><p><i>Is Feynmanium the last chemical element that can physically exist? That is, what are the chemical consequences of having an element with an atomic number above 137, whose 1s electrons must travel faster than the speed of light?</i> <a href="https://en.wikipedia.org/wiki/Extended_periodic_table#Elements_above_the_atomic_number_137" rel="nofollow">https://en.wikipedia.org/wiki/Extended_periodic_table#Elemen...</a>