Chemistry / Unit 2 Chem 0252 short lesson, about 20 seconds
Molecular Formula
Captions available
The idea
A molecular formula lists each element's symbol in a molecule along with a subscript giving the count of that element's atoms present.
In practice
Water's molecular formula, H2O, shows two hydrogen atoms bonded to one oxygen atom in every water molecule.
Where people slip
A missing subscript always means exactly one atom of that element — no implied "1" is ever written next to a symbol.
Your place on the trail
Every lesson rests on earlier ones and opens later ones. Tap any to jump.
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