which has the most acid coke or vinegar
I don't have any numbers to support my thinking but I know MOST brands of vinegar are 5% acetic acid (although I saw one recently at 4%). I think coke is about 0.05 M but I don't KNOW that. In addition, k1 for H2CO3 is much less than acetic acid (by a factor of about 100). Therefore, I think vinegar is a stronger acid (by a fair margin) than coke. I think I know of a site that lists pH of foods. If I can find it I will post it following this post.
I found two sites. The first one lists vinegar and the second list coke products.http://vm.cfsan.fda.gov/~mow/app3a.html
http://www.madsci.org/posts/archives/oct98/909181221.Ch.r.html