Here's how to calculate the number of moles of H atoms in 11.5 mol of H₂O:

1. Understand the Chemical Formula:

* H₂O tells us that each molecule of water contains 2 hydrogen atoms (H) and 1 oxygen atom (O).

2. Use the Mole Ratio:

* For every 1 mole of H₂O, there are 2 moles of H atoms.

3. Calculate:

* (11.5 mol H₂O) * (2 mol H / 1 mol H₂O) = 23 mol H

Therefore, there are 23 moles of H atoms in 11.5 moles of H₂O.