Why Are pH Values Only In A Range Of 0-14?

The pH scale is used to determine whether a substance is acidic or basic, and to calculate how strong a chemical it is. A pH value is a number that ranges from 1 to 14 for most common chemicals, with seven being the middle or neutral point. Values below 7 are indicators of acidity, which increases as the number decreases, while values above 7 indicate alkalinity, which increases as the value increases. An important distinction to understand is that the pH scale is a logarithmic scale. On this scale, a substance with a pH of 3 is ten times more acidic than a substance with a pH of 4, and 100 times more acidic than a substance with a pH of 5. Similarly, a substance with a pH of 9 is ten times more alkaline than a substance with a pH of 8, and 1000 times more alkaline than a substance with a pH of 6. Theoretically speaking, the pH scale should actually range from negative infinity to positive infinity. This claim is according to its definition, which states that the pH of a substance is the value defined by the negative logarithm of the hydrogen ion concentration. However, in reality, most solutions you would find in a standard laboratory have a pH value between 0-14.