Constants I Periodic Table Part A ou may want to reference (Pages 656-664) Secti
ID: 228282 • Letter: C
Question
Constants I Periodic Table Part A ou may want to reference (Pages 656-664) Section 5.8 while completing this problem. Find the equilibrium concentration of S2 Express the concentration to three significant figure Consider the reaction for the decomposition of hydrogen disulfide: 2H2S(g) 2H2 (g) +S2(g), Kc = 1.67 x 10-7 at 800°C The reaction is carried out at the same temperature with the following initial concentrations [H2S] = 4.30 x 10-4M [H21-0.00 M [S2] 0.00 M S2lValue its Submit Previous Answers
Explanation / Answer
The reaction is 2H2S(g) <------------> 2H2(g)+ S2(g)
Equilibrium constant = K= [S2] [H2]2/ [H2S]2= 1.67*10-7,
preparing the ICE table
component initial change equilibrium
H2S 4.3*10-4 -2x 4.3*10-4-2x
H2 0 2x 2x
S2 0 x x
K= x*(2x)2/ (4.3*10-4-2x)2= 1.67*10-7 ,
x3/(4.3*10-4-2x)2= 1.67*10-7/4= 4.2*10-8
when solved for x using excel, x= 1.87*10-5
hence at equilibrium, [S2]=1.87*10-5 M , [H2]=2*1.87*10-5= 3.74*10-5M, H2S= 4.3*10-4-2*1.87*10-5=0.0003926