Answer:
congratulations you have made cocaine
it would need to gain 2 more for it to achieve a stable configuration
the best way to remember this is the noble gasses all have 8 valence electrons and that they are the most stable elements on the periodic table
The question is asking to state the element would most likely have chemical properties similar to that of fluorine and base on my research and further investigation, I would say that it would be Bromine. I hope you are satisfied with my answer and feel free to ask for more if you have questions and further clarifications
Answer:
2K + Br2 --> 2KBr is the answer