How many liters of NH3, at STP, will react with 16.2 g O2 to form NO2 and water

Explanation:use molar mass to finf moles of O2: 5.3 g O2 32.0 g/mol = 0.1656 moles of O2 use this ratio: 4NH3 (g) + 7O2 (g) - ->, to find moles of NH3: 0.1656 mol O2 4 mole NH3 / 7 mol O2 = 0.09464 moles of NH3 using the "molar volume " ratio for gases STP, find the litres of NH3: 0.09464 moles NH3 22.4 litres / mole STP = 2.12 litres

answer: 2.1 litres