Q194ptsConsider the chemical reaction 2NHg N2g 3H2g The equ
     Q19.(4pts)--Consider the chemical reaction 2NH(g)  N2(g) + 3H2(g). The equi libriumis to be established in a 1.0 L container at 1,000 K, where K.-4.0 × 10-2. Initially, 1,220 moles of NHs(g) are present. Estimate the equilibrium concentration of H2(g)     
 
  
  Solution
Initial concentration of NH3=[NH3]o=1220 mol/1.0L=1220mol/L
ICE table
Kc=4.0*10^-2=[N2][H2]^3/[NH3]^2=(x)(3x)^3/(1220-2x)^2
4.0*10^-2=27x^4/(1220-2x)^2
Taking square root of both sides and solving for x,
X=3.0M
[H2]=3*x=9M
| [NH3] | [N2] | [H2] | |
| Initial | 1220M | 0 | 0 | 
| Change | -2x | +x | +3x | 
| Equilibrium | 1220M-2x | x | 3x | 

