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 Phthalic Acid
Chemical formula: C8H6O4
Also known as: ortho-phthalic acid
Phthalic Acid is Acidic
At concentration of 1 mM, it has a pH of 3.2
At concentration of 10 mM, it has a pH of 2.55
At concentration of 100 mM, it has a pH of 2