Sorry for the delayed reply, but I'm back to ask a couple more blood-related questions.
Which of the following would bubble if submerged in hydrogen peroxide: ketchup, paint, rust, barbeque sauce, and/or a fresh tomato (smashed). I know it has to do with which ones contain catalase, but Google's not being cooperative and isn't providing the answers easily.
Also, a couple posts back, rjb suggested that an LGM test could potentially be created by mixing malachite green, acetic acid distilled from vinegar, and zinc. Suppose my novel's character could come up with those three things -- would it be as easy as tossing all of them in a glass and stirring it up? The scene that I've conjured up so far is that my character is in a house and they find malachite green by the homeowner's fishtank; next, they distill some vinegar and mix it with the malachite in a glass, then drop a few pennies inside (US pennies are made of zinc apparently). Again, because of dramatic reasons, this character would not have time to run to the store to grab anything else and, since they don't have any presumptive tests handy, they must use things only found around the house. I can take some creative license (like finding malachite green by a fishtank), but I want it to be at least semi-believable. So I guess my main questions are: 1) How would they combine this solution? and 2) If these ingredients could work, what are some rough rough measurements? I.E. how pennies would be needed?
Thanks for continuing to field my odd questions!