Introduction to pH Scale

In a world of such various differences, human beings since the beginning of time have wanted to find ways to discover what makes said differences, different. Hot vs. cold, soft vs. hard, acid vs. base. For each of the named, we have methods of gauging the difference between one another, and the severity of said difference. For heat we have temperature, for hardness we have scales such as the Rockwell scale, and for acidity or basicness, we have the pH scale. Common examples of acids include from common household vinegar, to battery acid. On the contrary, for bases, we can find common Alka-Seltzer tablets, to chlorine. Soren P.L. Sörenson had so blessed us with his proposal of the pH scale, stating that “The added amount of acid would not necessarily be a true measure of its dissociation, depending on chemical interactions with other chemical species. Sörenson proposed that the actual degree of acidity should be rationally measured by hydrogen ion concentration.1” Without his direct contribution to the pH scale, which offers much simplicity, it would be profoundly more difficult to gauge acidity, in addition to basicness. Without this, the difference between Alka-Seltzer, which relies on an acid-base reaction to sooth acid related stomach ailments, and bleach, would not be so easily gauged. The pH scale works in the light of simplicity, where a 7 on the scale tells you a substance is neutral, anything below 6.9 towards 0 is increasingly acidic, and anything above 7.1 to 14 is increasingly basic. For example, battery acid would gauge 0, or very close to 0, while bleach, drain cleaner, and things of this sort gauge 14, or very close. The pH scale provides us with ease of use and simplicity, which when dealing with acids and bases, is very much handy.

*Sources:
1 http://www.corrosion-club.com/historypHscale.htm
2 Mrs. Melton’s excellent teaching :D