For the reaction system, h2(g) + x2(g) ↔ 2 hx(g), kc = 24.4 at 300 k. a system made up from these components which is at equilibrium contains 0.200 moles of x2 and 0.600 moles of hx in a 4.00 liter container. calculate the number of moles of h2(g) present at equilibrium.

0.0738 moles

Explanation:

1) Equilibrium chemical equation:

H₂(g) + X₂(g) ⇄ 2HX(g)

2) Equilibrium constant equation:

3) Concentrations:

Molarity = number of moles of sulute / volume of solution in liters

[H₂] = 0.200 mol / 4.00 liter = 0.0500 M

[HX] = 0.600 mol / 4.00 liter = 0.150 M

4) Replace the known concentrations into the Kc equation:

5) Solve for [X₂]

5) Convert the concentration to number of moles

number of moles = M×V = 0.0184M×4.00liter = 0.0738 moles

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