To be used as a conductor for heat
It is more likely to be found as a COMPOUND, as it is more reactive, by the time we found them, they're already reacted with other elements or compounds to form new compounds.
Example is oxygen, it is very reactive, therefore we often found oxygen in water, which is H2O, in earth, instead of just pure oxygen.
Actually Welcome to the concept of Atomic Structure.
Since, We all know that, To draw any Electron-Dot Structure, we always have to know the exact Number of valence or free electrons of any atom or molecule, hence
The Correct Answer is :-
D. Number of valence electrons.
Answer:20 million years ago
Explanation: