Today in my chemistry class we did a reaction with hcl and mg. Normally this should produce h2 which is odorless however, it smelled like rotten eggs which is caracteristic of MgS. What could have done this. We put a Mg ribbon in 1,0M ,2,0M ,3,0M and 4,0M HCl but it smelled Rotten eggs. After the experiment, some people including myself complained about a headache. So first of all, were we exposed at a too high level oh H2S, like should we do something about it or just let it go. The only symptoms were headche and a tiny eye irritation, the other higher exposure symptoms were not present so i guess we were only a little bit exposed and theres nothing we should do about it. However, my real question is HOW THE **** did we end up getting H2S from HCl and Mg? Did our teachers put Sulfur instead of Mg ribbons or what? Like the equation is Mg+2HCl=MgCl2+h2 so there is no H2S present in the reaction. did they put h2so4 instead of hcl? this really confuses me. Or might it be as i read somewhere due to impurities in the mg? I don't think this is the reason because impurities would probably be in a very low quantity so they would not have caused some headaches. I will ask the question to my teacher at my next class but for now, should i be worried about it? Was it bad to breathe a little bit of h2s or there is no real problem at these concentrations?
Please help me elucidate this mystery
Thank you for your help