Ammonium perchlorate (NH4CIO4) is a powerful solid rocket fuel, used in the Space Shuttle boosters. It decomposes into nitrogen (N2) gas, chlorine (Cl2) gas, oxygen (O2) gas and water vapor, releasing a great deal of energy. Calculate the moles of ammonium perchlorate needed to produce 2.00 mol of water. Be sure your answer has a unit symbol, if necessary, and round it to the correct number of significant digits.