Constants | Periodic Table Coal, which is primarily carbon, can be converted to
ID: 711591 • Letter: C
Question
Constants | Periodic Table Coal, which is primarily carbon, can be converted to natural gas, primarily CH 4 , by the following exothermic reaction. C(s)+2 H 2 (g) CH 4 (g) Part A Which of the following will favor CH 4 at equilibrium? Check all that apply. Check all that apply. adding more H 2 to the reaction mixture lowering the volume of the reaction mixture adding more C to the reaction mixture raising the temperature of the reaction mixture adding neon gas to the reaction mixture adding a catalyst to the reaction mixture
Explanation / Answer
The question can be understood by taking help of lechatlier's principle which states that a reaction in equilbrium will always try to undo the effect of stress applied to it. This stress can be temperature,volume,pressure,catalyst or any change in any of the reaction variables the equilbrium will counteract the said stress or change by shifting in the direction that results in nullification of the said change or stress
E.g. if temperature is increased for an endothermic reaction in equilbrium,the excess heat in the form of increased temperature will be absorbed & equilbrium will shift right towards products thereby nullifying the change(increase) in temperature.
In the above given reaction addition of more of hydrogen will subject the equilbrium to stress(increased pressure) & equilbrium will try to undo the stress by reaction of excess hydrogen to form product ch4 thereby eliminating the stress
If volume of reaction mixture is lowered then since three molecules of reactants are getting converted to 1 molecule of ch4 i.e. reaction proceeds from more volume to less volume side.lowering the volume will result in larger production of ch4.
Adding more of carbon will have the same effect as adding larger quantity of h2 i.e. equilbrium will shift right.
Since reaction is exothermic,raising temperature will discourage the formation of ch4.i.e. reaction will proceed towards lowering of temperature i.e. towards reactants.thus ch4 will dissocciate into c &2h2.
Adding of a catalyst generally lowers the activation energy of the reaction as such more of h2 & c will convert to products in presence of a catalyst.
At constant volume addition of neon will have no effect but at constant pressure the reaction will proceed to left.