Great quiz! It is a little hard to keep scrolling up and down, though. Maybe if the symbol was also listed at the bottom of the table, that would make it easier?
Have you taken this quiz on phone or desktop? The scrolling cannot be avoided on phone but I did my best to improve this for desktop user, generating 7 columns of answers. Can't see anything else to change.
I made a lot of misclicks, can the names of atoms be a bit more spaced? Though it would add more scrolling back and forth...
It would actually be simpler to simply type the names of the atoms, but I do not know if it can be done with this format of quizz.