Question

Please, I need help with gas stoichiometry.

Answer 1

Nitric acid is prepared commercially by the Ostwald process. In the first step of this process, ammonia gas is burned with oxygen in the presence of platinum to produce nitric oxide and water. The balanced chemical equation is given below.
4NH3 (l) + 5O2(g) 4NO (g) + 6H2O (l)
If all the gases in this reaction are at STP, what will be the volume of NO formed during the combustion of 1000 liters of NH3?

Answer 2

4NH3 (l) + 5O2(g) -> 4NO (g) + 6H2O (l)

In this problem is missing one data. To begin you need to convert the 1000 Liters of NH3 that according to the reaction is a liquid, to moles of NH3. To do this you have to know the value of the density of NH3. According to wikipedia the density of NH3 is 0.73 kg/m³= 0.73g/mL.
Density is mass over volume, then if you know that you have 1000L of NH3 and the density is 0.73 g/mL , you can calculate the mass of NH3 = density x volume
mass of NH3= 0.73 g/mL x 1000 x 10^3 mL = ???? g NH3

Then you can calculate the moles of NH3
n=m/MM
n= number of moles
m=mass
MM=Molecular Mass NH3 = 17 g/mol

The number of moles of NH3 are going to be the same number of the moles of NO because in the stoichiometry of the reaction the relationship is 4:4 (1:1)

Finally because the problem said that the gases are a STP conditions, the molar volume is going to be 22.4L. Then multiply the number of moles of NO x 22.4L to find out the liters of NO formed