Consider the formation of hydrogen fluoride: H 2 (g) + F 2 (g) 2HF(g) 1) If a 1.
ID: 941606 • Letter: C
Question
Consider the formation of hydrogen fluoride:
H2(g) + F2(g) 2HF(g)
1) If a 1.5 L nickel reaction container (glass cannot be used because it reacts with HF) filled with 0.0077 M H2 is connected to a 4.0 L container filled with 0.029 M F2. The equilibrium constant, Kp, is 7.8 x 1014 (Hint, this is a very large number, what does that imply?) Calculate the molar concentration of HF at equilibrium.
2) Suppose a 3.00 L nickel reaction container filled with 0.0098 M H2 is connected to a 4.00 L container filled with 0.229 M F2. Calculate the molar concentration of H2 at equilibrium.
Explanation / Answer
1)
H2(g) + F2(g) 2HF(g)
No of mol of H2 = 1.5*0.0077 = 0.01155 mol
No of mol of F2 = 4*0.029 = 0.116 mol
7.8*10^14 = (2x)^2 / ((0.116-x)(0.01155-x))
x = 0.01155 mol
concentration of HF = 0.01155 mol
2)
No of mol of H2 = 3*0.0098 = 0.0294 mol
No of mol of F2 = 4*0.229 = 0.916 mol
7.8*10^14 = (2x)^2 / ((0.0294-x)(0.916-x))
concentration of HF = 0.0294 mol