Chemically, a "strong acid" is one that dissociates completely in solution. HCl, H2SO4, HNO3, HBr, HI, HClO4, HClO3 comprise the complete list. That's it. Al

Chemically, a "strong acid" is one that dissociates completely in solution. HCl, H2SO4, HNO3, HBr, HI, HClO4, HClO3 comprise the complete list. That's it. All other acids have a dissociation constant, pKa. The pKa for acetic acid is 4.76 . It is a "weak acid", but then again, so is HF, with a pKa of 3.17 . If you have ever seen Breaking Bad, you have seen what even a "weak acid" can do to the human body at high concentrations. The usual story about acetic acid is that your chem prof was pipetting glacial acetic acid by mouth, and they accidentally got some in their mouth, and all the cells lining their oral cavity peeled off the next day. And they used bulbs or thumbwheel pumps on their pipettes ever since. Not sure if this story is especially common or if it is made up to scare students into using the lab equipment safely. But anyway, the point is that the ill effects for caustic chemicals are largely dependent on concentration. "Vinegar" is acetic acid diluted to between 4 wt% and 18 wt%. You can drink vinegar, and just have skin rashes and weak teeth. If you drink enough glacial acetic acid (>99 wt%), you're going to die.