Question

Gaseous ammonia chemically reacts with oxygen gas to produce nitrogen monoxide gas and water vapor. Calculate the moles of oxygen needed to produce of water. Be sure your answer has a unit symbol, if necessary, and round it to significant digits.

Answer 1

Answer: The correct answer will be 5 moles, because according to the  stoichiometric ratio, 5 moles of oxygen produce 6 moles of water.

Explanation:

The balanced equation is:

$4NH_{3} + 5O_{2}$ ⇒ $4NO + 6H_{2}O$

As you can see in the balanced reaction, it is necessary 5 moles of oxygen for obtain 6 moles of water. This stoichiometric ratio can be used for calculate any amount of produced water, once you have a specific amount of oxygen.