A precipitation reaction produces a sparingly soluble solid from species initially in solution. For example, mixing aqueous silver and chloride ions can give $\mathrm{A}{\mathrm{g}}^{+}+\mathrm{C}{\mathrm{l}}^{-}⟶\mathrm{AgCl}(\mathrm{s})$.

Formation of a solid depends on the activities of its ions relative to the solubility product, not simply on the names of the mixed salts. The precipitate removes dissolved species until an equilibrium condition is reached. This principle supports qualitative ion tests, gravimetric analysis, and separation of components from a mixture.^[ref]

A gas mixture contains more than one gaseous component. For an ideal mixture, each component contributes partial pressure $p_i=y_{i}P$, where $y_i$ is its mole fraction, and the partial pressures sum to total pressure.

Air provides a familiar example. Departures from ideal behavior require interaction-dependent quantities such as fugacity, while condensation can change the gas composition. A stated gas mixture therefore needs both composition and physical conditions.

Apparatus that rotates samples to separate components according to their sedimentation behaviour.

Executing work before a condition validating it is resolved. Correctness requires suppressing or recovering its architectural effects if the condition fails. A reorder buffer supports controlled instruction retirement of such work.

A processor with several CPU cores that can execute instruction streams concurrently. Shared computer memory requires attention to cache coherence and the architecture's memory model.

Executing ready instructions before older instructions whose operands or resources are unavailable, while preserving the specified architectural behavior. Reservation stations, register renaming and a reorder buffer support different parts of this organization.

A propagating spatial variation in cellular calcium concentration. Coupling local release and recovery to transport can produce pulses with rapid fronts and slower return to a resting state.

Particle physics studies the elementary constituents of matter and their interactions. It connects quantum fields and symmetry principles with measurements of scattering, decays and particle production.

An accelerator experiment does not photograph an elementary particle's internal form directly. Detectors record tracks, energy deposits and timing signals; a model reconstructs the event and compares distributions with predicted processes. Collider studies, neutrino measurements and nonaccelerator experiments provide complementary tests of the Standard Model and searches for additional phenomena.

Study of the form and organization of plant structures.

Characterization of cells through detectable molecular markers, often using antibodies. Marker combinations can distinguish populations, but expression of one marker alone does not establish every aspect of cellular identity.

A digitized volume of historical University of Oxford examinations. The First and Second Examination paper labels restart each year. Only the month and year are printed on the 1867 papers; page locators here refer to the PDF volume, not printed page numbers.

Original scan: upload.wikimedia.org/wikipedia/commons/3/3e/Examination_papers_for_the_Degree_of_Bachelor_of_medicine_-_1864-67_(IA_b24757810).pdf

Catalogue: wellcomecollection.org/works/d7b9zgnx

Wellcome Collection marks this digitized volume with the Public Domain Mark. The original was supplied by Royal College of Physicians, London. The original questions can therefore accompany the solutions here.^[ref]

Primary Greek text. II.7 opens with the coeliac affection of Aretaeus. The edition reads λείπει where the Oxford extract stops at λείπε- across the page break.

Translated primary excerpt, Selection 1, The Elements of Life, identifies four distinct fluids. The Hippocratic Corpus should not be assumed to have a single author.

Primary text, Book II.10 on bloodletting and II.11 on wet cupping and dry cupping.

Primary Greek text. Section 1 sets out successive decisions about depletion, tolerance, site, quantity and repetition.

Use the translated primary text, §§1019–1022, especially contraindications, timing and vessels for venesection, rather than the surrounding modern commentary. Edition catalogue: wellcomecollection.org/works/szf4vypc

Digitized primary printed calendar with institutional description. Lists supposedly suitable times for bloodletting using the patient and lunar phases.

Original historical research in Medical History 55(3), pp. 355–360, using contemporary texts and images. The discussion of François-Joseph-Victor Broussais relates local irritation, medicinal leeches and therapeutic theory.

Primary passages from the 1835 work, pp. 70–76, reproduced with translations and edition details. Includes early-versus-late bloodletting, age, and comparisons between groups.