Mistake Master
Home Unit 8 · Acids and Bases 8.1· 8.2· 8.3· 8.4· 8.5· 8.6· 8.7· 8.8· 8.9· 8.10· 8.11

Introduction to Acids and Bases

In the Brønsted-Lowry model, an acid donates a proton (H⁺) and a base accepts one. After the transfer, the acid becomes its conjugate base and the base its conjugate acid — a conjugate pair differs by exactly one proton. Water autoionizes slightly, so even pure water has equal H⁺ and OH⁻, with Kw = [H⁺][OH⁻] = 1.0 × 10⁻¹⁴ at 25 °C.

UNIT 8 TOPIC 8.1 • INTRODUCTION TO ACIDS AND BASES CONJUGATE PAIRS Proton transfer creates conjugate acid–base pairs that differ by exactly one H⁺. BRØNSTED–LOWRY ACID — donates a proton (H⁺), the H⁺ donor BASE — accepts a proton (H⁺), the H⁺ acceptor acid base conjugate base conjugate acid HA + B A⁻ + BH⁺ H⁺ transfers One proton moves from the acid to the base — giving two conjugate pairs. CONJUGATE PAIR 1 HA / A⁻ HA loses H⁺ to become A⁻. The acid and its conjugate base. Differ by exactly one proton (H⁺). CONJUGATE PAIR 2 B / BH⁺ B gains H⁺ to become BH⁺. The base and its conjugate acid. Differ by exactly one proton (H⁺). CED ANCHOR A conjugate acid–base pair differs by exactly one H⁺. Whichever way the reaction runs, HA/A⁻ and B/BH⁺ stay linked by proton transfer. AP Chemistry · Unit 8 · Acids and Bases
In the Brønsted-Lowry model, an acid donates a proton (becoming its conjugate base) and a base accepts one (becoming its conjugate acid). Water autoionizes slightly, so even pure water contains equal H⁺ and OH⁻ (Kw = [H⁺][OH⁻] = 1.0 × 10⁻¹⁴ at 25 °C).
Neutral Water · Open the sandbox →

The core skill is following the proton to name the acid, base, and their conjugates, and remembering that a substance's role can switch with its partner (water is amphoteric). Autoionization sets the neutral baseline that the pH scale is built on.

The work

3 ways in · any order
Lesson
Intro to Acids and Bases

Brønsted-Lowry acids donate protons and bases accept them, forming conjugate pairs, while water autoionizes. The lesson tracks the proton and conjugate pairs, then closes with a ten-scenario check.

Skill check · 10 scenarios
Diagnostic
10-item topic check

Ten items on the Brønsted-Lowry model: identifying the proton donor and acceptor, naming conjugate acid-base pairs, and the autoionization of water.

Not started · 10 items · ~15 min
Targeted Practice
Drill a single misconception

Pick one of the failure modes you missed and drill it on its own. The round is adaptive: two correct in a row clears the misconception and moves you to the next.

Take the diagnostic to identify your misconceptions