Which statement correctly pairs acidity types with pH ranges?

Which statement correctly pairs acidity types with pH ranges?

• A. Phenolphthalein acidity is prevalent below pH 4.3; Mineral acidity tends to be in the lower pH ranges.
• B. Phenolphthalein acidity is prevalent above pH 4.3, and mineral acidity tends to be in the lower pH ranges.
• C. Phenolphthalein acidity is prevalent below pH 4.3; Mineral acidity tends to be in the higher pH ranges.
• D. Phenolphthalein acidity is prevalent above pH 8.3; Mineral acidity tends to be in the lower pH ranges.

Answer: (B)

In water chemistry, acidity is characterized by the pH range over which the acids are active, distinguishing mineral acidity from phenolphthalein acidity. Mineral acidity comes from stronger inorganic acids and keeps the water’s pH in the lower end of the scale. Phenolphthalein acidity refers to the portion of acidity that is relevant when considering the higher-pH region associated with the phenolphthalein endpoint. Because of this, phenolphthalein acidity appears at pH values above a threshold around 4.3, while mineral acidity is observed at the lower pH ranges. The statement reflecting this—phenolphthalein acidity being prevalent above pH 4.3 and mineral acidity tending toward the lower pH ranges—accurately pairs the two acidity types with their typical pH ranges. The other options conflict with how these acidity types behave across the pH spectrum.

In water chemistry, acidity is characterized by the pH range over which the acids are active, distinguishing mineral acidity from phenolphthalein acidity. Mineral acidity comes from stronger inorganic acids and keeps the water’s pH in the lower end of the scale. Phenolphthalein acidity refers to the portion of acidity that is relevant when considering the higher-pH region associated with the phenolphthalein endpoint. Because of this, phenolphthalein acidity appears at pH values above a threshold around 4.3, while mineral acidity is observed at the lower pH ranges. The statement reflecting this—phenolphthalein acidity being prevalent above pH 4.3 and mineral acidity tending toward the lower pH ranges—accurately pairs the two acidity types with their typical pH ranges. The other options conflict with how these acidity types behave across the pH spectrum.