Inital rates question :)

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Rate question

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Experiment 2 and 3, [E] & [G] are constant. [F] doubles and rate doubles.
Because (reagent conc. Increase)order = rate increase, 2y=2 so order w.r.t. F must be 1.

Experiment 3 and 4, [E] increases by almost 12 times, [F] increases by a factor of 4 and [G] increases by 10 times. Rate increased by a factor of 575

So 12x x 41 x 10z = 575

Divide by 4 gives 12x x 10z = 144. Given that the orders w.r.t. the reactants must be 0,1 or 2. Then we have these possibilities….

x=0. z=0
x=1, z=0
x=2, z=0
x=0. z=1
x=1, z=1
x=2, z=1
x=0. z=2
x=1, z=2
x=2, z=2

Clearly the only way 12x x 10z can equal (via whole number power terms) is if x=2 and z=0 {note: 144 is 122 with no other contribution from the “ 10z “ term}

Hence order w.r.t.: F=1, E=2 and G=0

Rate equation = k[F]1[E]2[G]0 or simply rate = k[F]1[E]2

We could have done this via experiment 1 and two (and in fact would have been easier as the [F] is const. From expt. 1 to 2, [E] increases by a factor of (almost)6 times. [F] is constant, [G] increases by a factor of 5 times and the rate increases by a factor of 36. So, 6x x 5z = 36.   36 is 62 alone, so again we deduce x=2 and z=0

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