The ethyl alcohol in "gasohol" burns to form CO 2 and H 2O. If the combustion reaction consumes 6.645 moles of C 2H 5OH reacting with excess O 2, how many grams of H 2O are formed

359.3 g

Explanation:

Step 1: Write the balanced combustion reaction

C₂H₅OH + 3 O₂ ⇒ 2 CO₂ + 3 H₂O

Step 2: Calculate the moles of water formed from 6.645 moles of ethyl alcohol

The molar ratio of C₂H₅OH to H₂O is 1:3.

6.645 mol C₂H₅OH × (3 mol H₂O/1 mol C₂H₅OH) = 19.94 mol H₂O

Step 3: Calculate the mass corresponding to 19.94 moles of H₂O

The molar mass of H₂O is 18.02 g/mol.

19.94 mol × 18.02 g/mol = 359.3 g