Uploaded February 2014 | Updated September 2026, 1 hour ago
Mr. Key uses average atomic mass to explain why the mass number on the periodic table has a decimal.
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.
Mr. Key uses average atomic mass to explain why the mass number on the periodic table has a decimal.
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.
