How many moles of `O` are present in `4.9 g` of `H_(3) PO_(4)`? (Atomic weight of `P, O` and `H = 31, 16, 1`)

Explanation

To determine how many moles of oxygen are present in 4.9 g of H₃PO₄, we will follow these steps:

### Step 1: Calculate the molecular weight of H₃PO₄
The molecular weight of H₃PO₄ can be calculated by adding the atomic weights of its constituent elements:

- Hydrogen (H): 3 atoms × 1 g/mol = 3 g/mol
- Phosphorus (P): 1 atom × 31 g/mol = 31 g/mol
- Oxygen (O): 4 atoms × 16 g/mol = 64 g/mol
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