In a sample of which of these elements would you expect to find a sea of electrons surrounding nuclei? . a) ar. b) au. c) o. d) n.

B) Au

Explanation:

Electron sea model:-

It assumes that the electron of the metal atoms tends to flow between the nuclei of the metal easily.  

It is model which shows the metallic bonding in which the cations of the metal are at the fixed places and the negatively charged electrons move freely within them.  

Since, out of the given options, Au is the only metal and it only has metallic bond which has a sea of electrons. Thus, answer is:- B) Au

answer : a model is often used to explain and make things easier to understand when any scientific topic needs to be demonstrated and explained.

as in this case where a scientist wants to use a model to present the results of his detailed scientific investigation. he should do it as it will him to make the audience understand the concept in a much better way. also, it can be changed according to new scientific understandings.