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A blood vessel is a tubular structure conducting blood within the circulatory system. Its endothelium and supporting wall differ among arteries, capillaries and veins. Conduction, exchange and volume storage are therefore emphasized differently in different vessel classes.
The pulmonary circulation carries blood from the right heart through the lungs and back to the left heart. It supports exchange of oxygen and carbon dioxide. Its pressure load differs from the systemic circulation even though long-term net flow through both circuits must balance.
A chemical equation expressing reacting ionic species explicitly, with spectator ions omitted in a net ionic equation.
A conventional class of chemical elements with properties intermediate between those commonly associated with metals and nonmetals; its membership is not a fundamental sharp boundary.
The chemical element identified spectroscopically through a characteristic green line in 1861.
A solid chemical compound whose composition can vary within a range through structural defects or variable site occupancy.
Barium chloride is , providing barium cations and chloride anions in aqueous solution. Hydrated and anhydrous solids differ in their water content and molar mass.
Addition of sulfate can produce sparingly soluble barium sulfate. This makes barium chloride useful in qualitative sulfate tests, provided competing precipitates and the solution conditions are controlled.
[ref]
Chemistry 2e by Paul Flowers and others. Chemical equations, oxidation-state conventions and solution equilibria; chapters4,14–17
The potassium salt of ferricyanide, historically red prussiate of potash.
The potassium salt containing the ferrocyanide complex, historically yellow prussiate of potash.
An anion containing chlorine in oxidation state , or a salt containing it. Historical ferric “perchloride” is a chloride, not a perchlorate.
Allyl isothiocyanate has the connectivity . The organic group is attached through nitrogen to the isothiocyanate unit, distinguishing it from an alkyl thiocyanate.
It is a major pungent constituent of black-mustard volatile oil. The structure combines an allyl double bond with a separate nitrogen-carbon-sulfur reactive group, so these sites must be distinguished when discussing a reaction.
[ref]
Organic Chemistry by John McMurry. Organic functional groups and connectivity: isothiocyanate versus thiocyanate
Hydrogen sulfide is , a bent molecular compound of hydrogen and sulfur. In water it participates in acid-base equilibria involving hydrosulfide and sulfide.
Its sulfur can undergo redox transformations and bind many metal ions. Formation of sparingly soluble metal sulfides links its solution chemistry to precipitation and mineral formation.
Barium hydroxide is and can also occur as hydrated crystals. Its dissolved fraction supplies hydroxide ions and behaves as a strong base.
It is important to distinguish solubility from base strength: the former concerns how much solid dissolves, whereas the latter concerns the acid-base behaviour of the dissolved species. Reaction with carbon dioxide can form barium carbonate.
Barium carbonate is the salt , containing barium and carbonate ions. It has low solubility in water, but reaction with an acid consumes carbonate and can release carbon dioxide.
Precipitation and acid dissolution therefore describe different conditions for the same material. This is a useful example of how acid-base chemistry can shift a solubility equilibrium.
Lead sulfide is , a compound of lead and sulfur that occurs naturally as galena. Its crystalline structure is related to that of sodium chloride.
Lead sulfide is also a semiconductor. Crystal size can strongly affect the optical response of very small particles, making the material an example of the connection between bulk band structure and quantum confinement.
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!
Intro to OurBigBook
. Source. We have two killer features:
- 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-calculusArticles 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/derivativeVideo 2. OurBigBook Web topics demo. Source. - 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.
- to OurBigBook.com to get awesome multi-user features like topics and likes
- as HTML files to a static website, which you can host yourself for free on many external providers like GitHub Pages, and remain in full control
Figure 2. You can publish local OurBigBook lightweight markup files to either OurBigBook.com or as a static website.
Figure 3. Visual Studio Code extension installation.
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. 
- Infinitely deep tables of contents:
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