Step 1:
\First chemical reaction is
\2CO(g) + O2(g) <====> 2CO2(g) Equation (1)
\The reaction take place at temperature 25°C and equilibrium constant .
Second chemical reaction is
\CO2(g) <====> CO(g) + 1/2 O2(g) Equation (2)
\The reaction take place at temperature 25°C and equilibrium constant .
Find equilibrium constant for second reaction :
Reverse the first equation .
\\ \ 2CO2(g) <====> 2CO(g) + O2(g)
\If an equation is reversed Kc is inverted : Kc2 = 1/Kc1 .
\Divide the coefficients of second equation by 2. \ \ CO2(g) <====> CO(g) + 1/2 O2(g) \ \ If the coefficients are divided by 2, then take the square root of Kc.
\Therefore the equilibrium constant for second reaction is
Substitute equilibrium constant of first reaction.
\ \
So the equilibrium constant is . \ \
Option A is correct choice . \ \
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