Ammonia, NH3, reacts with Oxygen to form NO and water. If 12.0 g of ammonia is allowed to react with 15.0 grams of oxygen, what will be the amount of excess
reactant remaining after the experiment is complete?

Yes she is correct. the answer is completely correct

If a hydrogen atom is neutral, it must also have  one electron. an oxygen atom (o) has an atomic number of eight (8). this means a neutral oxygen atom has eight protons and eight electrons. the element actium (ac) has an atomic number of 89, so it has 89 protons and 89 electrons in a neutral atom

So what you would do is go through and add 3 teaspoons(tsp) 6 times because of the 6 tablespoons(tbsp). which will give you an answer of 18. another way is to multiply 3x6=18.

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