Here's how to calculate the number of moles in 117g of H2O:

1. Find the molar mass of water (H2O):

* Hydrogen (H) has a molar mass of approximately 1 g/mol.

* Oxygen (O) has a molar mass of approximately 16 g/mol.

* So, the molar mass of H2O is (2 * 1 g/mol) + 16 g/mol = 18 g/mol.

2. Use the formula: moles = mass / molar mass

* moles = 117 g / 18 g/mol

* moles = 6.5 mol

Therefore, there are 6.5 moles in 117g of H2O.