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.

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:

⇒

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.

23.5

23.5

47.0

your answer is a. the enthalpy of formation for a pure element in its standard state is always positive.