Naturally, other friends asked her for specific details about what she was using, so she came back a while later and posted the "recipe" - powdered comet, vinegar, and bleach.
The recipe was met with further "I can't wait to try that!" comments, which sounds like a logical following for a recommendation that will take precious minutes off of a cleaning routine. Unfortunately for these excited posters, mixing bleach and vinegar is a dangerous thing to do. What happens when you mix bleach and vinegar? Why, you get chlorine gas.
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Then, of course, you get someone else who comments on your warning comment that that really isn't the case, and that the only thing you have to worry about is mixing bleach and ammonia. Unfortunately for her, my materials engineer husband and Dr. Google both confirmed that mixing bleach and vinegar does, in fact create chlorine gas. Guess I wasn't sleeping through all of high school chemistry, after all.
So here's my daily tip: Don't take random internet advice at face value. Do your own research, especially when it comes to things like mixing household chemicals and things like that. Otherwise you'll just end up hurting yourself.