Answer
Last option --> V = 9.96 L
Explanation
Given
A balanced chemical equation
[tex]6NO\text{ + 4NH}_3\rightarrow\text{ 5N}_2+6H_2O[/tex]
Mass of NO = 20.0 g
at STP: Pressure = 1 atm, temperature = 273 K
Required: Volume of NH3 gas
Solution
Step 1: Find the moles of NO
n = m/M where n is the moles, m is the mass and M is the molar mass
n = 20.0 g/30,01 g/mol
n = 0.666 mol
Step 2: Use stoichiometry to calculate the moles of NH3
The molar ratio between NO and NH3 is 6:4
Therefore the moles of NH3 = 0.666 x (4/6) = 0.444 mol
Step 3: Calculate the volume of NH3
PV = nRT
Re-arrange to solve for V
V = nRT/P
V = (0.444 mol x 0.0821 L.atm/K.mol x 273 K)/1 atm
V = 9.96 L
