[icasekingx]

I am currently in a first year chemistry class and one of our experiments was to combine Sodium Sulfite with 6 M HCl and record the results. I understand that when you combine the two it creates SO2 gas. Myself, being inexperienced with chemistry labs, took about 1/2 a sniff of the test tube and almost nearly passed out next to my lab partner. I understand that SO2 gas is quite toxic(now I find that out) when it comes to long term exposure, but my question to anyone who is qualified to answer is... how much SO2 was I exposed to when I took a sniff of this foul smelling gas? Should I be concerned with the level of toxicity i was exposed to? I am a bit worried and overwhelmed by this.  It really caught me off guard.

Thanks for your response in advance.

[UnintentionalChaos]

I doubt you were exposed to very much. Sodium sulfite is @167g/mol (even more if it is the hydrate) and you probably had no more than a gram or so in the test tube (being a qualitative demonstration lab). Given these conditions, and assuming all the gas escaped the test tube (which it didn't, some surely stayed dissolved), only about 135mls of gas would have been formed. I wouldn't really worry about it given the scale of the experiment. Next time gently "waft" some of the fumes toward yourself so you can smell it in low concentraion. It should have smelled like burnt matches. If it smelled like rotten eggs, there was a sulfide present and H2S is a noxious poison, worse than hydrogen cyanide.

[icasekingx]

Thanks for your prompt reply.
I was using roughly a pea sized amount of sodium sulfite and around 10-12 drops of HCl. I must admit it was quite overwhelming how intensely the smell got to me...