5.1.3 – Acids, Bases and Buffers - Definitions Flashcards
(24 cards)
What is the Acid Dissociation Constant (Ka)?
The extent of acid dissociation. pKa = -log(Ka) and Ka = 10^(-pKa
Define a Brønsted-Lowry Acid
A proton donor
Define a Brønsted-Lowry Base
A proton acceptor
What is a Buffer Solution?
A system that minimizes pH change on addition of small amounts of an acid or base
Describe the Carbonic Acid-Hydrogencarbonate Buffer
The buffer system present in blood plasma, used to maintain blood pH between 7.35 and 7.45
What is a Conjugate Acid-Base Pair?
A pair of compounds that transform into each other by the transfer of a proton
Define a Dibasic Acid
An acid that can donate 2 hydrogen atoms per molecule of the acid
Define the Equivalence Point
The point during a titration when the amount of acid is exactly equal to the amount of base
What is an Indicator?
A weak acid that changes colour with changing pH due to an equilibrium shift between HA and A-
What is an Ionic Equation?
A chemical equation that involves dissociated ions
Define the Ionic Product of Water (Kw)
The temperature-dependent constant that represents the dissociation of water into H⁺ and OH⁻
What is the End Point in a titration?
The point during a titration when the indicator changes colour
Define the Equivalence Point
The point during a titration when the amount of acid is exactly equal to the amount of base
What is an Indicator?
A weak acid that changes colour with changing pH due to an equilibrium shift between HA and A⁻
What is an Ionic Equation?
A chemical equation that involves dissociated ions
Define the Ionic Product of Water (Kw)
The temperature-dependent constant that represents the dissociation of water into H⁺ and OH⁻.
What is a Monobasic Acid?
An acid that can donate 1 hydrogen atom per molecule of acid
Define pH
A way of communicating the concentration of hydrogen ions. pH = -log[H⁺] and [H⁺] = 10^(-pH)
What is a pH Meter?
An instrument used to measure the pH of a solution
What does Strength of Acids and Bases refer to?
A measure of the relative degree of dissociation of an acid or base
Define Titration
A technique used to determine the amount of one solution of known concentration required to completely react with a known volume of another solution of unknown concentration
What are Titration Curves?
A graph which shows the change in pH over the course of a titration
Define a Tribasic Acid
An acid that can donate 3 hydrogen atoms per molecule of acid
What is the Vertical Section in a titration curve?
The vertical part of a titration curve which contains the equivalence point for the titration
