Acids and Bases

• Acids and bases are fundamental chemical concepts that describe proton transfer reactions and solution chemistry in aqueous systems.
• The Brønsted-Lowry describes acids as proton donors and bases as proton acceptors in chemical reactions.
• pH is the negative logarithm of the hydrogen ion concentration, providing a scale from 0-14 to measure acidity and basicity.
• Ka is the acid dissociation constant that quantifies the strength of an acid by measuring its degree of ionization.
• Kb is the base dissociation constant that quantifies the strength of a base by measuring its degree of ionization.
• pKa is the negative logarithm of the acid dissociation constant, with lower pKa values indicating stronger acids.
• pKb is the negative logarithm of the base dissociation constant, with lower pKb values indicating stronger bases.
• Buffers are solutions that resist changes in pH when small amounts of acid or base are added, consisting of weak acid-conjugate base pairs.
• Titration is an analytical technique where a solution of known concentration is gradually added to determine the concentration of another solution.
• The equivalence point in a titration is reached when the moles of acid equal the moles of base added.
• Indicators are compounds that change color at specific pH ranges, used to detect the endpoint of titrations.
• Neutralization reactions occur when acids and bases react to form salt and water, with the pH moving toward 7.
• Strong acid completely ionizes in aqueous solution, releasing all available protons and having very low pKa values.
• Weak acid only partially ionizes in aqueous solution, establishing an equilibrium between ionized and unionized forms.
• Conjugate pairs are acid-base pairs that differ by a single proton, related through proton transfer reactions.

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