1. School of Chemical Engineering, Xi'an University, Xi'an 710065,China;
2. College of Chemistry and Chemical Engineering, Shaanxi Normal University, Xi'an 710119, China
Abstract The concept of pH and its test method were first introduced by the Danish biochemist, Soren Peter Lauritz Sorensen, in 1909. This scale for measuring acidity and alkalinity ensured the unity of product quality and flavor in the beer manufacturing industry then. Due to its obscure origin in chemistry, there are certain misunderstandings about the idea of pH in domestic and international chemistry teaching, which leads to the problematic use of unclear chemical knowledge and the pH test paper. By reviewing this history, we can restore its original connotation and promote the development of chemical teaching norms.
