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Chemistry help

Hi, I am stuck on some Chemistry homework, the question is: Explain how we know there are no missing elements in the first 10 elements of the periodic table. I’m guessing it is something to do with protons, electrons and neutrons, which links to atomic and mass number. However I am not sure how i can use those to find an answer, i would appreciate some help :smile:

(edited 9 months ago)

Reply 1

difficultrooster

I think because an what element an atom is depends on the number of protons in the nucleus (as different isotopes of the same element have different number of neutrons) and the atomic number is the number of protons; we know there are no missing elements in the first 10 elements as the atomic numbers are consecutive starting from 1.
(different numbers of electrons affects whether its an atom or an ion/the ions charge)

i hope this makes sense, i wasnt quite sure how to word it :smile:

Reply 2

Moonlight:)