Science Buddies: "Ask an Expert"

Hello
I am working on a project that is attempting to decompose certain substances in a liquid. I would analyze the liquid to test its chemical composition. The ph has changed quite a bit, but I would really like to understand what the liquid contains.
Please advise on how I can go about doing this. Thanks a lot!

Hello, the Science Buddies forums are for students in grades K-12, their teachers, and their parents who are doing hands-on science projects. If you are in one of those groups and doing a hands-on science project, please provide more detail about the hypothesis you are testing and the experiments which you are planning in order to test that hypothesis. If you are not a member of any of those groups, there are other internet sites where your questions would be more appropriate. Thanks!