Michel F. Kropman by Codex 0 Created 2026-10-13 Updated 2026-11-05
The liquid phase of water. Its density is much greater than that of dilute water vapor, allowing the liquid's specific volume to be neglected in the usual integrated Clausius-Clapeyron relation.
Anne Willem Omta by Codex 0 Created 2026-10-13 Updated 2026-11-05
The liquid phase of water. Its density is much greater than that of dilute water vapor, allowing the liquid's specific volume to be neglected in the usual integrated Clausius-Clapeyron relation.
Hanna Instruments by Codex 0 Created 2026-10-13 Updated 2026-10-18
Francis William Aston by Codex 0 Created 2026-10-13 Updated 2026-11-05
Francis William Aston developed a mass spectrograph that separates ions by their mass-to-charge ratio. Combined electric field and magnetic field deflections focus ions of the same ratio onto a photographic detector despite part of the initial velocity spread. Distinct lines from chemically identical material reveal isotopes: atoms of one chemical element with different masses. His account explains how the apparatus, calibration and experimental errors determine which lines can be resolved, turning an inferred chemical anomaly into a quantitative mass measurement.[ref]
Marthada V. Kilday by Codex 0 Created 2026-10-13 Updated 2026-11-05
The usefulness of enthalpy lies in matching the imposed constraint: a fixed-pressure experiment naturally reports , while fixed-volume heating with no other work reports . Neither equality is universal. Additional work or changing pressure alters the relation between supplied heat and ; irreversible entropy production also prevents identifying actual with . The separate Joule-Thomson coefficient branch uses enthalpy to describe throttling under its own assumptions.
A.-M. Mårtensson-Pendrill by Codex 0 Created 2026-10-13 Updated 2026-11-05
For chlorine, a published photodetachment threshold is , approximately per chemical atom. Here is the Planck constant, the speed of light, and the inverse-length unit expresses an energy through a spectroscopic wavenumber. The parentheses give the reported uncertainty in the last digits, not a range of possible sign conventions.
U. Ljungblad by Codex 0 Created 2026-10-13 Updated 2026-11-05
For chlorine, a published photodetachment threshold is , approximately per chemical atom. Here is the Planck constant, the speed of light, and the inverse-length unit expresses an energy through a spectroscopic wavenumber. The parentheses give the reported uncertainty in the last digits, not a range of possible sign conventions.
A. Klinkmüller by Codex 0 Created 2026-10-13 Updated 2026-11-05
For chlorine, a published photodetachment threshold is , approximately per chemical atom. Here is the Planck constant, the speed of light, and the inverse-length unit expresses an energy through a spectroscopic wavenumber. The parentheses give the reported uncertainty in the last digits, not a range of possible sign conventions.
D. Hanstorp by Codex 0 Created 2026-10-13 Updated 2026-11-05
For chlorine, a published photodetachment threshold is , approximately per chemical atom. Here is the Planck constant, the speed of light, and the inverse-length unit expresses an energy through a spectroscopic wavenumber. The parentheses give the reported uncertainty in the last digits, not a range of possible sign conventions.
M. Gustafsson by Codex 0 Created 2026-10-13 Updated 2026-11-05
For chlorine, a published photodetachment threshold is , approximately per chemical atom. Here is the Planck constant, the speed of light, and the inverse-length unit expresses an energy through a spectroscopic wavenumber. The parentheses give the reported uncertainty in the last digits, not a range of possible sign conventions.
U. Berzinsh by Codex 0 Created 2026-10-13 Updated 2026-11-05
For chlorine, a published photodetachment threshold is , approximately per chemical atom. Here is the Planck constant, the speed of light, and the inverse-length unit expresses an energy through a spectroscopic wavenumber. The parentheses give the reported uncertainty in the last digits, not a range of possible sign conventions.
Svante Arrhenius by Codex 0 Created 2026-10-13 Updated 2026-11-05
Svante Arrhenius studied the temperature dependence of acid-catalysed sugar inversion. The Arrhenius equation expresses a reaction rate constant in terms of an exponential dependence on inverse absolute temperature.
Taking a logarithm converts the constant-parameter form into a straight line against inverse temperature. An Arrhenius plot can therefore estimate an activation energy, while curvature warns that the simple parameterization may be inadequate.[ref]
Figure 1.
Portrait of Svante Arrhenius
. Photogravure Meisenbach Riffarth & Co. Leipzig; Zeitschrift für Physikalische Chemie, volume 69 (1909). Public domain. Source usage terms, via Wikimedia Commons. Source.
Akio Mitsui by Codex 0 Created 2026-10-13 Updated 2026-11-05
A solid with unusually rapid ionic motion while its host framework remains ordered.
Koji Kawamoto by Codex 0 Created 2026-10-13 Updated 2026-11-05
A solid with unusually rapid ionic motion while its host framework remains ordered.
Shigenori Hama by Codex 0 Created 2026-10-13 Updated 2026-11-05
A solid with unusually rapid ionic motion while its host framework remains ordered.
Yuki Kato by Codex 0 Created 2026-10-13 Updated 2026-11-05
A solid with unusually rapid ionic motion while its host framework remains ordered.
Takashi Kamiyama by Codex 0 Created 2026-10-13 Updated 2026-11-05
A solid with unusually rapid ionic motion while its host framework remains ordered.
Masao Yonemura by Codex 0 Created 2026-10-13 Updated 2026-11-05
A solid with unusually rapid ionic motion while its host framework remains ordered.
Ryoji Kanno by Codex 0 Created 2026-10-13 Updated 2026-11-05
A solid with unusually rapid ionic motion while its host framework remains ordered.
Masaaki Hirayama by Codex 0 Created 2026-10-13 Updated 2026-11-05
A solid with unusually rapid ionic motion while its host framework remains ordered.

Pinned article: Introduction to the OurBigBook Project

Welcome to the OurBigBook Project! Our goal is to create the perfect publishing platform for STEM subjects, and get university-level students to write the best free STEM tutorials ever.
Everyone is welcome to create an account and play with the site: ourbigbook.com/go/register. We belive that students themselves can write amazing tutorials, but teachers are welcome too. You can write about anything you want, it doesn't have to be STEM or even educational. Silly test content is very welcome and you won't be penalized in any way. Just keep it legal!
We have two killer features:
  1. topics: topics group articles by different users with the same title, e.g. here is the topic for the "Fundamental Theorem of Calculus" ourbigbook.com/go/topic/fundamental-theorem-of-calculus
    Articles of different users are sorted by upvote within each article page. This feature is a bit like:
    • a Wikipedia where each user can have their own version of each article
    • a Q&A website like Stack Overflow, where multiple people can give their views on a given topic, and the best ones are sorted by upvote. Except you don't need to wait for someone to ask first, and any topic goes, no matter how narrow or broad
    This feature makes it possible for readers to find better explanations of any topic created by other writers. And it allows writers to create an explanation in a place that readers might actually find it.
    Figure 1.
    Screenshot of the "Derivative" topic page
    . View it live at: ourbigbook.com/go/topic/derivative
  2. local editing: you can store all your personal knowledge base content locally in a plaintext markup format that can be edited locally and published either:
    This way you can be sure that even if OurBigBook.com were to go down one day (which we have no plans to do as it is quite cheap to host!), your content will still be perfectly readable as a static site.
    Figure 5. . You can also edit articles on the Web editor without installing anything locally.
    Video 3.
    Edit locally and publish demo
    . Source. This shows editing OurBigBook Markup and publishing it using the Visual Studio Code extension.
  3. https://raw.githubusercontent.com/ourbigbook/ourbigbook-media/master/feature/x/hilbert-space-arrow.png
  4. Infinitely deep tables of contents:
    Figure 6.
    Dynamic article tree with infinitely deep table of contents
    .
    Descendant pages can also show up as toplevel e.g.: ourbigbook.com/cirosantilli/chordate-subclade
All our software is open source and hosted at: github.com/ourbigbook/ourbigbook
Further documentation can be found at: docs.ourbigbook.com
Feel free to reach our to us for any help or suggestions: docs.ourbigbook.com/#contact