Methanol. The change in standard free energy for the synthesis of liquid methanol from gaseous carbon monoxide and hydrogen is -29 kJ/mole of methanol. Write the balanced reaction equation, the equilibrium constant expression?

This involves Gibbs Free Energy but I do not know how to solve this.

1 Answer
Ernest Z.
Mar 29, 2018

Here's what I get.

Explanation:

The balanced equation

#"CO(g) + 2H"_2"(g)" → "CH"_3"OH(l)"; Δ_text(r)G^@ = "-29 kJ·mol"^"-1"#

The equilibrium constant expression

#K_text(p) = 1/(p_text(CO)p_text(H₂)^2)#

The equilibrium constant

#ΔG^@ = "-"RTlnK#

#lnK = -(ΔG^@)/(RT) = -("-29 000" color(red)(cancel(color(black)("J.mol"^"-1"))) )/(8.314 color(red)(cancel(color(black)("J·K"^"-1""mol"^"-1"))) × 298 color(red)(cancel(color(black)("K")))) = 11.7#

#k = e^11.7 = 1.2 × 10^5#

Related questions
Impact of this question
3473 views around the world
You can reuse this answer
Creative Commons License