M5S5 – Calculating Mole Fractions

Consider the synthesis of methanol in the following equilibrium:

CO_(g) + 2H_2(g) <=>CH₃OH_(g)

2.00 mol of CO was mixed with 4.00 mol of H₂ and the mixture sealed in a container. The mixture was left until no further observable change in composition took place. At this point, 1.90 mol of CH₃OH was present in the mixture.

Calculate the value of the mole fraction of CH₃OH present in the mixture under these conditions.

Consider the following equilibrium:

N_2(g) + O_2(g) <=>2NO_(g)

1.80 x 10^-3 mol of N₂ was mixed with 2.40 x 10^-3 mol of O₂ and 7.20 x 10^-3 mol of NO and the mixture sealed in a container. The mixture was left until no further observable change in composition took place. At this point, 4.80 x 10^-3 mol of O₂ was present in the mixture.

Calculate the value of the mole fraction of O₂ present in the mixture under these conditions.

Consider the following equilibrium for the reaction that generates hydrogen for use in the Haber-Bosch Process:

CH_4(g) + H₂O_(g) <=>CO_(g) + 3H_2(g)

140 mol of CH₄ was mixed with 100 mol of H₂O and the mixture given time to reach equilibrium. At this point, 240 mol of H₂ was present in the mixture.

Calculate the value of the mole fraction of CH₄ present in the mixture under these conditions.

Consider the following equilibrium for the Haber-Bosch process:

3H_2(g) + N_2(g) <=>2NH_3(g)

6.00 mol of H₂ was combined with 6.00 mol of N₂ and the mixture sealed in a heated and pressurised vessel with an iron catalyst. The mixture was left until no further observable change in composition took place. At this point, 3.00 mol of NH₃ was found to be present in the mixture.

Calculate the value of the mole fraction of NH₃ present in the mixture under these conditions.

Consider the following equilibrium:

2SO_2(g) + O_2(g) <=>2SO_3(g)

35.0 mol of 2SO₂ was mixed with 22.5 mol of O₂ and the mixture sealed in a heated vessel with vanadium (V) oxide catalyst. The mixture was left until no further observable change in composition took place. At this point, 15.0 mol of O₂ was present in the mixture.

Calculate the value of the mole fraction of SO₃ present in the mixture under these conditions

Consider the following homogenius gaseous equilibrium:

ethene + steam <=> ethanol

0.180 mol of ethene as mixed with 1.03 mol of steam and the the mixture heated in the presence of a catalyst. The mixture was sealed in a vessel and allowed to reach equilibrium. At equilibrium, 0.110 mol of ethanol was present in the equilibrium mixture.

Calculate the value of the mole fraction of ethanol present in the mixture under these conditions.

Consider the following equilibrium:

H_2(g) + I_2(g)<=>2HI_(g)

1.50 mol of HI was placed in a sealed vessel and allowed to decompose. At equilibrium, 0.500 mol of HI remained in the vessel

Calculate the value of the mole fraction of HI present in the mixture under these conditions.

Consider the following equilibrium:

PCl_3(g) + Cl_2(g) <=> PCl_5(g)

6.00 mol of PCl₃was mixed with 6.00 mol of Cl₂ and the mixture sealed in a vessel and allowed to reach equilibrium. At equilibrium, 2.00 mol of PCl₅ was present in the equilibrium mixture.

Calculate the value of the mole fraction of PCl₅ present in the mixture under these conditions.