Answer : The total mass of oxygen gas released in the reaction will be, 12.8 grams
Explanation :
Law of conservation of mass : It states that mass can neither be created nor be destroyed but it can only be transformed from one form to another form.
This also means that total mass on the reactant side must be equal to the total mass on the product side.
The balanced chemical reaction will be,

According to the law of conservation of mass,
Total mass of reactant side = Total mass of product side
Total mass of
= Total mass of 
or,
Total mass of
= Mass of
+ Mass of 
As we are given :
Total mass of
= 16.12 grams
The mass of
= 9.72 grams
So,
Total mass of
= Mass of
+ Mass of 


Therefore, the total mass of oxygen gas released in the reaction will be, 12.8 grams
Answer : 51.8 g of nitrogen are needed to produce 100 grams of ammonia gas.
Solution : Given,
Mass of
= 100 g
Molar mass of
= 27 g/mole
Molar mass of
= 28 g/mole
First we have to calculate moles of
.

The given balanced chemical reaction is,

From the given reaction, we conclude that
2 moles of
produced from 1 mole of 
3.7 moles of
produced from
of 
Now we have to calculate the mass of
.
Mass of
= Moles of
× Molar mass of 
Mass of
= 1.85 mole × 28 g/mole = 51.8 g
Therefore, 51.8 g of nitrogen are needed to produce 100 grams of ammonia gas.
There chemical reactions that can realise or absorb gas to the atmosphere. This means it is harder or impossible to measure it with normal weighing devices and normal taring equipment. As a principal in chemical reactions we have conservation of mass.
i believe
2 g/mL
good luck!
I believe the answer is C: "<span>It occurs when a hydrogen atom bonds with electropositive atoms."</span>