The equation tells us that for every 8 moles of HNO3 that react, 4 moles of H2O are produced. So we need to first convert the 8 grams of HNO3 to moles and then find the number of moles of H2O produced.
Using the molar mass of HNO3 (63.0 g/mol), we find:
8 g HNO3 / 63.0 g/mol = 0.127 mol HNO3
Since 4 moles of H2O are produced for every 8 moles of HNO3, the number of moles of H2O produced would be:
0.127 mol HNO3 * (4 moles H2O / 8 moles HNO3) = 0.064 mol H2O
Finally, to find the mass of H2O produced, we use the molar mass of H2O (18.0 g/mol):
0.064 mol H2O * 18.0 g/mol = 1.16 g H2O
So, when 8 grams of HNO3 are consumed, approximately 1.16 grams of H2O can be made. Round to the nearest tenth, the answer is 1.2