The given reaction is :
CO(g)+H2O(g)⇌CO2(g)+H2(g)
We are given that
40% of water by mass reacts with carbon monoxide.
The molecular weight of water (H
2O) is approximately
18g/mol, so
1mole of water weighs
18g. Therefore, the mass of the reacted water is
0.40×18g=7.2g.
Since from the stoichiometry of the reaction we can see that
1mole of CO reacts with
1mole of H
2O to form
1mole of CO
2 and
1mole of H
2, this means that
7.2g of H
2O is equivalent to
7.2g/18g/mol=0.4mole.
We start with
1mole of CO and
1mole of H2O. At equilibrium, we have :
- CO:
1mole−0.4mole=0.6mole
- H
2O :
1mole−0.4mole=0.6mole
- CO
2 :
0mole+0.4mole=0.4mole
- H
2 :
0mole+0.4mole=0.4mole
The volume of the container is
10litres. Therefore, we can convert the moles to concentrations (in M = moles/L) as :
- [CO] =
0.6M
- [H
2O] =
0.6M
- [CO
2] =
0.4M
- [H
2] =
0.4M
The equilibrium constant
Kc for the reaction can be calculated as :
Kc=[CO][H2O][CO2][H2]
So, substituting the values we get :
Kc=(0.6×0.6)(0.4×0.4)=0.44
As per the question, we need to calculate the value of
Kc×102 :
Kc×102=0.44×102=44(rounded to the nearest integer)
Therefore,
Kc×102=44.