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in reversible reactions based on Le Chatelier's principle the effect of concentration?

Le-Chatelier's principle
 
   If a dynamic equilibrium is distributed by changing the conditions ,the position of equilibrium moves to counteract the change / if a chemical substance at equilibrium experiences a change in concentration,temperature,volume ,or partial pressure, then the equilibrium shifts to counteract the imposed change and a new equilibrium is established. Changing the concentration of a constituent will shift the equilibrium to the side that would reduce the change in concentration .the system will have a tendency to oppose the change. In turn ,the rate of reaction ,extent and yield of products will be changed corresponding to the impact on the system .
     Consider the reaction of CO and H2 ,reacting to form methanol .
           CO  +   2H2  ?  CH3OH   
   Suppose if we increase the concentration of CO in the system .Using Le -Chatelier's principle ,we can predict the amount of methanol will increase ,decreasing the total change in CO .If we are to add a species to the overall reaction ,the reaction will favor the side opposing the addition of species .Similarly ,the subtraction of species would cause the reaction to fill the gap and favor the side where the species was reduced .


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