## atomic weight, molecular weight, and formula weight

Sophia Dinh 1D
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Joined: Thu Jul 25, 2019 12:15 am

### atomic weight, molecular weight, and formula weight

How are atomic weight, molecular weight, and formula weight different?

Chem_Mod
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### Re: atomic weight, molecular weight, and formula weight

The atomic weight is the mass when only considering atoms themselves. Molecular weight is the sum of the component atom's masses using the compound's molecular formula. The formula weight is typically used for the empirical formula mass. In other words, molecular weight is a sum of the atomic weights.

Hailey Kim 4G
Posts: 110
Joined: Sat Jul 20, 2019 12:16 am

### Re: atomic weight, molecular weight, and formula weight

Atomic weight, or atomic mass, is the mass of an atom. For example, the atomic mass of hydrogen is 1.008 u. Molecular mass is the mass of the molecule as a whole. It is the sum of the atomic weight of each of the atoms in the molecule. For this, we would use the molecular formula. Formula mass is when we would use the empirical formula and take the sum of the atomic weight of the atoms used in that formula.