AP Chemistry Flashcards: Introduction to Acids and Bases
Written by AP Content Team, Verified for 2026 AP Exams, Last updated: May 2026
Review key ideas with interactive flashcards. This set includes 11 cards to help you master important concepts.
Why might the pH of pure, neutral water not be exactly 7.0?
The pH of pure, neutral water will deviate from 7.0 if its temperature is not 25°C, because the value of Kw is temperature-dependent.
Card 1 of 11
All Flashcards (11)
Why might the pH of pure, neutral water not be exactly 7.0?
The pH of pure, neutral water will deviate from 7.0 if its temperature is not 25°C, because the value of Kw is temperature-dependent.
What is the mathematical definition of pOH?
pOH is the negative base-10 logarithm of the hydroxide ion concentration, expressed by the formula pOH = -log[OH-].
Define the ion-product constant for water (Kw) and state its value at 25°C.
Kw is the equilibrium constant for water's autoionization, defined as Kw = [H3O+][OH−]. At 25°C, Kw equals 1.0 x 10^-14.
What are the specific values of pH and pOH for a neutral solution at 25°C?
In a neutral solution at 25°C, both the pH and the pOH are equal to 7.0.
What is the mathematical definition of pH?
pH is the negative base-10 logarithm of the hydronium ion concentration, expressed by the formula pH = -log[H3O+].
In a neutral solution of water at 25°C, what are the concentrations of H3O+ and OH-?
Based on Kw = 1.0 x 10^-14, the concentrations of both [H3O+] and [OH−] in a neutral solution at this temperature are 1.0 x 10^-7 M.
What defines a neutral solution in terms of pH and pOH?
In a neutral solution, the concentration of H3O+ equals the concentration of OH-, which means that pH = pOH.
What is the relationship between pKw, pH, and pOH at 25°C?
At 25°C, the sum of pH and pOH is equal to pKw, which has a value of 14.0.
Describe the autoionization of water.
Water undergoes autoionization, an equilibrium process where it reacts with itself to form hydronium ions [H3O+] and hydroxide ions [OH−].
How does temperature affect the ion-product constant for water, Kw?
The value of Kw is temperature-dependent, meaning it changes as the temperature of the water changes.
How are the symbols H+ and H3O+ used in the context of acids?
The symbols for the hydrogen ion (H+) and the hydronium ion (H3O+) are used interchangeably to represent the acidic species in an aqueous solution.