Few questions about equilibria:
1. Predict the effect of the changes on the position of each equilibrium: Removal of 
from the equilibrium: 
2. For the exothermic reaction: 
, how would you alter the temperature of the equilibrium in order to product a net forward reaction? I understand that because the forward reaction is exothermic, but what has this to do with decreasing the temperature to produce the forward reaction?
3. An equilibrium mixture containing: 
The volume of the container was increased at constant temperature and a new equilibrium was established. How would the concentration of 
be altered? I would say that because the pressure is being decreased, the more particles (moles) is favourable, and hence the forward reaction would increase and so the production of would increase. That being said, although the particles of nitrogen dioxide are being relatively increased, the volume is also increasing so does this actually mean that the concentration is increasing ?
Cheers.
1. If I had a solution of ethanoic acid, hydronium and acetate ions and I removed acetate, the concentration of acetate would decrease. Now imagine the backward reaction. Think of the backward reaction as any normal reaction. So if I removed the acetate ions, I remove reactants, and if I removed reactants, I reduce the chance of successful collisions occurring and so reaction rate decreases. So if the backward reaction occurs less frequently, more reactants will be converted to products, causing the forward reaction to occur to a greater extent --> Shifts in favour of forward reaction.
2. Reaction is exothermic. So, backward reaction is endothermic. Adding temperature= adding energy. Since the reaction is exothermic, energy is released, and so adding energy has no effect on the exothermic reaction other than increasing reaction rate.
On the other hand, when the reaction is endothermic, adding energy facilitates the reaction.So if I increased the temperature, the reaction has more energy to absorb from the environment, thereby causing the backward reaction to occur more frequently.Now, if I wanted to increase the yield of the forward reaction, I need to prevent the backward reaction from occurring. One way I can do this is by decreasing the temperature to prevent the backward reaction from occurring (although it may affect reaction rate).
3. Increase volume--> Decrease pressure--> Initial decrease in concentration--> Forward reaction occurs to greater extent due to particles--> Gradual increase in nitrogen dioxide concentration, gradual decrease in dinitrogen tetroxide concentration.
I'm confused about changing the equilibrium position. My text says that by adding reactant (or imposing any other change excluding temperature) a new equilibrium is established. Does this mean there is a new value of K?
No. K value is only changed by temperature. Adding reactants or products will partially offset the dynamic equilibrium. The position of equilibrium will thereby shift to counteract the change and create a new equilibrium with different concentrations of products and reactants but same K value.
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