AP BIOLOGY

Detailed explanation-1: -The range goes from 0-14, with 7 being neutral. pHs of less than 7 indicate acidity, whereas a pH of greater than 7 indicates a base. pH is really a measure of the relative amount of free hydrogen and hydroxyl ions in the water.

Detailed explanation-2: -Hence a range of 0 to 14 provides sensible (but not absolute) “bookends” for the scale. One can go somewhat below zero and somewhat above 14 in water, because the concentrations of hydronium ions or hydroxide ions can exceed one molar. Figure 1 depicts the pH scale with common solutions and where they are on the scale.

Detailed explanation-3: -Objects that are not very acidic are called basic. The scale has values ranging from zero (the most acidic) to 14 (the most basic). As you can see from the pH scale above, pure water has a pH value of 7.

Detailed explanation-4: -This is because, in order to reach pH levels below 0 or above 14, one would require extraordinarily acidic or basic solutions, respectively. A saturated sodium hydroxide solution (NaOH) solution is supposed to have a pH of 15 based on its molarity.