Answer to Question #61749 in Inorganic Chemistry for bharat

Question

Why were the compounds
of noble gases discovered late
? Why do noble gases
form
compounds
only
with oxygen and fluorine
?

Answer 1

1. Noble gases were discovered later than other elements, because they were extremely un-reactive. Being inert, they were difficult to isolate via chemical reactions, thus difficult to distinguish as separate elements.
2. Noble gases form compounds with fluorine and oxygen, because of comparable ionization energy. Noble gases have very low-energy, small outer orbitals, so they need similar partner to interact. Fluorine and oxygen have lowest-energy valence orbitals, so they give relatively stable compounds with noble gases.