Acid-base Equilibrium Flashcards
What is the definition of an acid?
A substance that donates protons or accepts electrons.
What is the definition of a base?
A substance that accepts protons or donates electrons.
What is the formula for the dissociation of water?
H2O ⇌ H+ + OH-
What is the equation for the autoprotolysis of water?
2H2O ⇌ H3O+ + OH-
What is the pH scale used for?
Measuring the acidity or basicity of a solution.
What is the pH of a neutral solution?
pH 7
What is the pH of an acidic solution?
pH less than 7
What is the pH of a basic solution?
pH greater than 7
What is the equation for calculating pH?
pH = -log[H+]
What is the equation for calculating pOH?
pOH = -log[OH-]
What is the relationship between pH and pOH in a solution?
pH + pOH = 14
What is the definition of a buffer solution?
A solution that resists changes in pH when small amounts of acid or base are added.
What is the Henderson-Hasselbalch equation used for?
Calculating the pH of a buffer solution.
What is the formula for the Henderson-Hasselbalch equation?
pH = pKa + log([A-]/[HA])
What is the common ion effect in a buffer solution?
The shift in equilibrium caused by the presence of an ion common to both the weak acid and its conjugate base.
What is the Kw value for water at 25°C?
Kw = 1.0 x 10^-14
What is the relationship between Ka and Kb for a conjugate acid-base pair?
Ka x Kb = Kw
What is the definition of a polyprotic acid?
An acid that can donate more than one proton.
What is the definition of amphiprotic species?
Species that can act as either an acid or a base.
What is the relationship between pKa and acidity of a compound?
The lower the pKa value, the stronger the acid.
What is the relationship between Ka and acid strength?
The larger the Ka value, the stronger the acid.
What is the definition of the acid dissociation constant, Ka?
A measure of the strength of an acid in solution.
What is the definition of the base dissociation constant, Kb?
A measure of the strength of a base in solution.
What is the relationship between pKa and Ka?
pKa = -log(Ka)
What is the relationship between pKb and Kb?
pKb = -log(Kb)
What is the definition of a Lewis acid?
A substance that accepts a pair of electrons.
What is the definition of a Lewis base?
A substance that donates a pair of electrons.
What is the definition of a Bronsted-Lowry acid?
A substance that donates a proton.
What is the definition of a Bronsted-Lowry base?
A substance that accepts a proton.
What is the definition of a conjugate acid-base pair?
Two species related by the donation and acceptance of a proton.
What is the definition of a strong acid?
An acid that completely dissociates in water.
What is the definition of a weak acid?
An acid that partially dissociates in water.
What is the definition of a strong base?
A base that completely dissociates in water.
What is the definition of a weak base?
A base that partially dissociates in water.
What is the definition of an amphoteric substance?
A substance that can act as both an acid and a base.
What is the definition of a neutralization reaction?
A reaction between an acid and a base to form water and a salt.
What is the definition of the equivalence point in a titration?
The point at which the moles of acid and base are stoichiometrically equivalent.
What is the definition of the end point in a titration?
The point at which the indicator changes color, signaling the completion of the reaction.
What is the definition of a titration curve?
A plot of pH versus volume of titrant added during a titration.
What is the definition of a salt in chemistry?
An ionic compound formed by the reaction of an acid and a base.
What is the definition of the solubility product constant, Ksp?
The equilibrium constant for the dissolution of a sparingly soluble salt.
What is the common ion effect in solubility equilibria?
The decrease in solubility of a salt due to the presence of a common ion.
What is the definition of a complex ion?
An ion formed by the coordination of a central metal ion with ligands.
What is the definition of a ligand in coordination chemistry?
A molecule or ion that donates a pair of electrons to a central metal ion.
What is the definition of a chelating agent?
A ligand that forms a complex with a metal ion using multiple donor atoms.
Acid periodic trend