Clear, accurate chemistry definitions 1,509 terms 6 topics 118-element periodic table

Free Term-of-the-Day Widget

Put a fresh chemistry definition on your class page or website every day. One copy-paste, no account, no maintenance — the term rotates automatically from our dictionary of 1,509 terms.

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Chemistry term of the day
Atomic Mass

Atomic mass is the weighted average mass of an element's naturally occurring isotopes. It considers both the exact weight and the natural abundance of each isotope. You can find this decimal number below the element symbol on…

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The widget is free for any website, including school and classroom pages. Please keep the credit link to chemistry-dictionary.com intact — it is how the widget pays for itself. The card is self-contained and will not affect your page styles; the definition changes once a day, automatically.

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