- A chemical compound is a chemical substance composed of many identical molecules (or molecular entities) containing atoms from more than one chemical element held together by chemical bonds. A molecule consisting of atoms of only one element is therefore not a compound. A compound can be transformed into a different substance by a chemical reaction, which may involve interactions with other substances. In this process, bonds between atoms may be broken and/or new bonds formed.
- The Illusions Index (illusionsindex.org)
The Illusions Index is a fully searchable, interactive curated collection of illusions. The illusions are categorised into different types, allowing you to search for, and compare, illusions that fall under one or more type. Staff and students at the Centre for the Study of Perceptual Experience have researched each illusion to provide detailed information about what it teaches us about the philosophy and psychology of perception.