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Ch.15 - Chemical Kinetics

Chapter 15, Problem 40e

A reaction in which A, B, and C react to form products is zero order in A, one-half order in B, and second order in C. e. By what factor does the reaction rate change if [C] is doubled (and the other reactant concentrations are held constant)?

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Hello, everyone. Today, we have the following problem. A reaction in which Xy and Z react to form products is first order in X one have order and Y and third order in Z by what factor is the reaction rate change if Z or the concentration of Z is tripled and the other reactant concentrations are held constant. And so we have your choices. ABC and D with a saying three BS six C sing nine and D sing 12. So wind drying out the rate low, we write that the rate is equal to a constant K. And then we put our first reactor in brackets. It was stated that as in first order. So we don't need to put an exponent there. We move on to our concentration of why putting it in brackets? It was stated as one half order. So we put an exponent of one half. And then lastly, we have our concentration of Z which we put in brackets and it was stated that it was third order. So we put an exponent of three. So if Z is tripled, then we have so if Z is triple, we have a three, Z So what would that look like? Well, we would have our rate equaling the same constant K multiplied by the same concentrations of Y and X or X and Y. And then we just have a three Z race of the power of three. Now we use the rule of exponents such that when we have an exponent outside of bra brackets or parentheses, we must apply that exponent to every variable inside of that. So for example, we have three Z raise the power of three. So you must have three race to the power of three and the race, the power of three. And so when we combine that, we get that the rate is equal to K multiplied by the same concentration of X and Y. And this time we have nine Z race of the power of three. Now also note that this nine could apply to that rate constant case such that we have the nine multiplied by the entire reaction. And so if you look at edge choices, we see that the reaction rate changes by a factor of nine overall, I hope it helped. And until next time.