Calculate the mass of 2.5 g atom of oxygen.

Explanation

To calculate the mass of 2.5 gram atoms of oxygen, we can follow these steps:

### Step 1: Understand the concept of gram atoms
A gram atom is the amount of a substance that contains the same number of entities (atoms, molecules, etc.) as there are in 12 grams of carbon-12. The mass of one gram atom of an element is numerically equal to its atomic or molecular mass in grams.

### Step 2: Identify the molecular mass of oxygen
The molecular mass of oxygen (O) is 16 g/mol. This means that one mole of oxygen atoms has a mass of 16 grams.

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