(This example is purely hypothetical.)
You have the reaction $$\ce{H2(g) + O2(g) <=> H2O2(g)}$$
at $T = 500\ \mathrm{K}$. The reaction reaches equilibrium at the following concentrations:
$$\ce{[H2]} = \ce{[O2]} = 5 \times 10^{-3}\ \mathrm{mol\ dm^{-3}}$$ $$\ce{[H2O2]} = 4\times10^{-5}\ \mathrm{mol\ dm^{-3}}$$
This gives $$K_c = \left(\frac{\ce{[H2O2]}}{\ce{[H2][O2]}}\right) = 1.6$$
However, the total concentration of the reactants is $250$ times higher than the concentration of the product.
Still, as $K_c > 1$, per definition, the products are favored.
This seems counterintuitive to me, and my Chemistry teacher couldn't really explain it to me, so I was hoping someone here could explain why, even when the reactants are so much more plentiful, the products are considered to be favored.
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