<em><u>Answer:</u></em>
Potassium.
<u><em>Explanation:</em></u>
Therefore, the answer is Potassium. You might think, that because we were talking about Argon as well, the answer is both of them, but no. Everything starts with Potassium but it decays into Argon during the process.
FeS is an example of an ionic compound as in the formula there is a metal of Fe iron chemically bonded to the nonmetal S sulphur. Resulting in a strong electrostatic attraction due to the transfer of valence electrons from the iron to the Sulphur.
Answer:
a..312 I guesss kkkkkkkkkkkkkkkkkk
I believe it would be the color Red.