Question

Why silver and gold do not react with oxygen even at high temperature?

Answer 1

Yes Silver and gold do not react with oxygen even at high temperatures as they are less reactive and are placed below the reactivity series. Hence they are called noble metals.
But silver fades after some months or years due to its tendency to react with sulphur in air forming their sulphides. Silver reacts with hydrogen sulphide in the air silver forms silver sulphide (Ag2S) which is responsible for the black coating on silver.

But gold pretty much doesn't react with almost anything it normally comes in contact with and stays untarnished. Gold is unaffected by air, water, alkalis and all acids except aqua regia (a mixture of hydrochloric acid and nitric acid) which can dissolve gold. Gold does react with halogens.

Answer 2

HEY MATE!!!

■Because of a special stability in full and half-full orbitals. 

■ Silver and gold have a single outer electron.

■ This is disadvantageous, energy-wise,when you look at the orbitals the electrons are in. The lone electron is in an S-orbital.

■ This orbital is thus half full (since s-orbitals can contain 2 electrons), whereas all the other inner orbitals in silver and gold are filled, and hence exceptionally stable.

■ After a full orbital, the next most stable orbital is a half full one. 

■ With this stability, they are most likely won't form any compound in normal and natural conditions, that's why gold ussually found in its native form. 

■ If you don't learn about the electron configuration yet, and do not understand what I mean, the answer is simply : Because Gold and Silver is very stable and less reactive.

■ So they most likely to exist natively than form compound with oxygen. 

■ Even in industry, high temperature of heating is needed to make Gold Oxide due to the stability of the atom

HOPE IT HELPS YOU!!!!