This little website shows you the pH of various acids, bases, food products, bodily fluids, cleaners, and more!
Here's a random substance:
pH of Nonanoic Acid
Chemical formula: C9H18O2
Also known as: pelargonic acid
Nonanoic Acid is Acidic
At concentration of 1 mM, it has a pH of 4
At concentration of 10 mM, it has a pH of 3.49
At concentration of 100 mM, it has a pH of 2.98