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A complete second-semester general chemistry course, built from OpenStax Chemistry 2e chapters 11 through 21 and the C-ID CHEM 120S transfer descriptor. It picks up where General Chemistry I leaves off: solutions and colligative properties open the course, then kinetics, chemical equilibrium, acids and bases, buffers and titrations, and solubility equilibria carry the middle third, followed by thermodynamics and electrochemistry, the two most math-heavy units. The course closes with a short survey of main-group and transition-metal descriptive chemistry, nuclear chemistry, and a brief bridge into organic chemistry for anyone continuing to that class. About a quarter of the cards are worked calculations (rate laws, ICE tables, pH and Henderson-Hasselbalch, Ksp, Gibbs free energy, the Nernst equation, nuclear half-life), each independently recomputed before publishing.
Deliberately short - continue into the full Organic Chemistry class for depth.
Copied straight from the course. In the app, each wrong option also gets its own explanation.
Card 1A concentration cell has E degree = 0. Why can it still generate a measurable voltage?
Because its measured E comes entirely from the ln Q term, from the concentration gap. With E degree = 0, the Nernst equation reduces to E = -(RT/nF) ln Q, so any voltage produced comes purely from the concentration-driven ln Q term.
Card 2Why do chemists usually measure initial rate rather than a rate measured well after the reaction has started?
Because at t = 0 no product has built up and no reverse reaction is occurring yet. Measuring the rate at the very start avoids complications from accumulating products or a developing reverse reaction, giving the cleanest data for determining the rate law.
Card 3Which expression correctly gives Ksp for the salt Ca3(PO4)2 dissolving as Ca3(PO4)2(s) <=> 3 Ca^2+ + 2 PO4^3-?
[Ca2+]^3[PO4^3-]^2. Ksp is the product of ion concentrations each raised to its stoichiometric coefficient: [Ca2+]^3[PO4^3-]^2.
Yes. Create a free Encodr account and all 12 units and 1,146 cards are yours to study, with spaced repetition scheduling your reviews.
This course assumes first-semester general chemistry (atoms, bonding, stoichiometry, gases, intermolecular forces). Solutions and colligative properties, the opening unit, leans on the intermolecular-forces chapter from General Chemistry I.
OpenStax Chemistry 2e chapters 11 through 21: solutions, kinetics, chemical equilibrium, acids and bases, buffers and titrations, solubility and complex-ion equilibria, thermodynamics, electrochemistry, main-group and transition-metal descriptive chemistry, nuclear chemistry, and a short bridge into organic chemistry.
About a quarter of the cards are worked calculations: rate laws and half-life, K and Q, ICE tables, pH/pKa/Henderson-Hasselbalch, Ksp and molar solubility, Gibbs free energy, the Nernst equation and Faraday's law, and nuclear decay half-life. Every numeric card states its rounding rule and was independently recomputed before publishing.
No. Unit 12 is a short bridge (hydrocarbons, functional groups, naming basics) that hands off to the full Organic Chemistry class on Encodr for real depth.