Uploaded February 2017 | Updated September 2026, 2 hours ago

---

Mr. Key compares covalent and ionic bonds in order to explain why particles of salt are referred to as formula units and not molecules.

Please note that all questions, comments and critiques are welcome. However, because the primary purpose of these videos is educational for students/educators, the comments are moderated. Any comments that are deemed abusive, inappropriate, or unrelated to the topic matter will not be posted and the user potentially blocked.