AP BIOLOGY

Detailed explanation-1: -The pH scale is logarithmic and inversely indicates the concentration of hydrogen ions in the solution. where M = mol dm−3. At 25 °C (77°F), solutions with a pH less than 7 are acidic, and solutions with a pH greater than 7 are basic.

Detailed explanation-2: -The pH scale covers the active concentration of the H+ ions and OH-ions and therefore the pH unit of measure is defined as the negative common logarithm of the active hydrogen ion concentration in an aqueous solution. If the H+ ion concentration changes by a factor of ten, the pH value changes by one unit.

Detailed explanation-3: -The pH scale is used to rank solutions in terms of how acidic or how basic they are. It indicates the concentration of hydrogen ions (H+) and hydroxide ions (OH-) in a solution. These ion concentrations are equal in pure water, which has a pH of 7.

Detailed explanation-4: -1: The pH scale is a logarithmic scale based on the concentration of hydrogen ions. The higher the H+ ion concentration is, the lower the pH of the solution. The pH scale is generally presented as running from 0 to 14, though it is possible to have a pH of less than 0 or greater than 14.