Consider the following equilibrium: Ag⁺(aq) + Cl^-(aq) ⇌ AgCl(s) Use Le Châtelier's principle to predict how the amount of solid silver chloride will change when the equilibrium is disturbed by: (d) Removing Cl^-; also account for the change using the reaction quotient Q_c

Video transcript

hi everyone for this problem. It reads according to lash outliers principle, how will the amount of solid zinc bromide change when the equilibrium of the fallen reaction is disturbed by removing the bromide ion, how does the change in the amount of bromide ion affect the reaction quotient of the reaction. Okay, so here we're dealing with lush outliers principle. And according to lash outliers principle. If we disturb an equilibrium system or chemical reaction, the system will readjust to maintain its equilibrium state. And so for this reaction, we want to know how does the change in the amount of bromide ion affect the reaction quotient? So let's go ahead and take a look at our problem. When we look at our problem, we'll see that the bromide ion is a reactant. Okay. If we remove a reactant, the reaction will shift towards the left and when it shifts towards the left it's going to produce more reactant and the amount of zinc bromide, which is the product will decrease. Okay. And so we need to write a equilibrium expression for our reaction quotient and our reaction quotient is represented here. And what this is is the concentration of products over the concentration of reactant. Okay. And what we're going to do with this is we're going to compare the reaction quotient to the equilibrium constant. Okay. And what will need to recall? Is that a reaction quotient. Q and equilibrium constant. K represent two different things and when Q is equal to K. That means the system is at equilibrium. When Q is larger than K. Let's see when Q is larger than K. That means the system is going to shift right or sift left. Excuse me. And when Q is less than K, the system is going to shift right? Alright, so let's go ahead and write our reaction quotient or Q. Okay. And we're going to need to recall our reaction for this. Okay, so we have in our reaction Aquarius, Aquarius and solid and pure solids or liquids are excluded from the equilibrium expression because they're effective concentration stay constant throughout the reaction. So that means for our concentration of products, since this is a solid, this is going to be one. And for our reactant since it's going to be the concentration of the zinc to ion times the concentration of the bromide ion. Okay, so since our reaction quotient is inversely proportional to the amount of bromide ion. So let's look at our expression here. So our reaction quotient is inversely proportional to the amount of bromide ion. That means the reaction quotient will increase and be greater than K. C. R equilibrium constant when bromide ion is removed at equilibrium. Okay, so our answer here is going to be that our reaction quotient Q is going to be larger than K. So the reaction is going to shift in the reverse direction or shift a left to right to reach equilibrium. And the reasoning behind that is because of that inverse proportionality. So we're looking at our reaction quotient Q. C and we're looking at where our bromide ion falls within our expression and it's in the denominator. So that means it's inversely proportional to the amount of bromide ion. So the reaction quotient will increase and be greater than the equilibrium constant K. When bromide ion is removed equilibrium, that is going to be the answer for this problem, and that is it for this problem.