Question

A) The synthesis of methanol from carbon monoxide and hydrogen gas is described by the following chemical equation:

CO(g)+2H2(g)⇌CH3OH(g)

The equilibrium constant for this reaction at 25 ∘Cis Kc=2.3×104. In this trial, you will use the equilibrium-constant expression to find the concentration of methanol at equilibrium, given the concentration of the reactants.

Suppose that the molar concentrations for CO and H2 at equilibrium are [CO] = 0.04 M and [H2] = 0.04 M.

Use the formula you found in Part B to calculate the concentration of CH3OH.

B) Consider the reaction:
CO(g)+H2O(g)⇌CO2(g)+H2(g)
An equilibrium mixture of this reaction at a certain temperature was found to have [CO]= 0.0213 M , [H2O]= 0.0115 M , [CO2]= 0.190 M , and [H2]= 0.0324 M .

What is the value of the equilibrium constant at this temperature?

C)An equilibrium mixture of the following reaction was found to have [I2]= 0.0225 M at 1200 ∘C.

What is the concentration of  I ?
I2(g)⇌2I(g)
Keq= 1.2×10⁻² at 1200 ∘C

Answer 1

1.For the reaction CO(g)+ 2H2(g)<---->CH3OH(g)

K= Equilibrium constant = [CH3OH]/[CO] [H2]² =2.3*10⁴ ,

Given [CO]=0.04M and [H2]=0.04M

[CH3OH] = 2.3*10⁴*0.04*0.04*0.04=1.472M

2. For the reaction CO(g)+ H2O(g)<--->àCO2(g)+ H2(g)

K= Equilibrium constant = [CO2][H2]/[CO] [H2O]

Given [CO]=0.0213M and [H2O]=0.0115M, [CO2] =0.19 and [H2] = 0.0324

K= 0.19*0.0324/(0.0213*0.0115) =25.13

3. for the reaction I2(g)<--->2I(g)

K= [I]²/[I2] = 1.2*10^-2

[I2] =0.0225

[I]²= 1.2*10^-2*0.0225, [I] =0.016432M