(a) Calculate the relative molecular mass of water `(H_(2)O)`. (b) Calculate the molecular mass of `HNO_(3)`.

Explanation

To solve the problem, we will calculate the relative molecular mass of water (H₂O) and the molecular mass of nitric acid (HNO₃) step by step.

### (a) Calculate the relative molecular mass of water (H₂O)

**Step 1: Identify the atomic masses of the elements in H₂O.**
- Atomic mass of Hydrogen (H) = 1 U
- Atomic mass of Oxygen (O) = 16 U

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