18. What is the stoichiometric coefficient for water when the following equation showing the combustion of propanol is balanced with the smallest whole number coefficients? C_(3)H_(7)OH+O_(2)arrow CO_(2)+H_(2)O A) 3 B) 8 C) 13 D) 4 E) 1

To balance the equation, we need to ensure that the number of atoms of each element is the same on both sides of the equation.Let's start by balancing the carbon atoms. There are 3 carbon atoms in propanol and 1 carbon atom in carbon dioxide. To balance the carbon atoms, we need to have 3 carbon dioxide molecules on the right side of the equation. The equation now looks like this: Next, let's balance the hydrogen atoms. There are 8 hydrogen atoms in propanol and 2 hydrogen atoms in water. To balance the hydrogen atoms, we need to have 4 water molecules on the right side of the equation. The equation now looks like this: Finally, let's balance the oxygen atoms. There are 1 oxygen atom in propanol, 2 oxygen atoms in each carbon dioxide molecule, and 1 oxygen atom in each water molecule. To balance the oxygen atoms, we need to have 5 oxygen molecules on the left side of the equation. The equation now looks like this: The stoichiometric coefficient for water in the balanced equation is 4. Therefore, the correct answer is D) 4.