sapling #7

[Bethany Yang 2E]

For the reaction

2A(g)+2B(g)+C(g)⟶3G(g)+4F(g)

the initial rate data in the table was collected, where [A]0 , [B]0 , and [C]0 are the initial concentrations of A , B , and C , respectively.

Experiment [A]0 (mmol⋅L−1) [B]0 (mmol⋅L−1) [C]0 (mmol⋅L−1) Initial rate (mmol⋅L−1⋅s−1)
1 19.0 125.0 280.0 5.94
2 38.0 125.0 210.0 11.9
3 38.0 250.0 70.0 47.5
4 19.0 125.0 140.0 5.94

ah sorry! can someone help me figure out the order, rate law, and rate constant? i keep getting it wrong :(

[Aliya 1H]

Hey!

1.) So, we can start first by determining the order for C in the rate law. Since we don't see C remain constant in two rxns, we can infer that it does not affect the rate of the rxn. For C, l=0.

2.) Then, we can look at A. Dr. Lavelle explained the sure-fire way to determine the order of species in lecture by using two lines of the table for rate=k[A]^n[B]^m[C]^l, but we can also do it as I'm about to explain, which is a little quicker than writing everything out. If you look at experiments 1 and 2, the concentration of A doubles (while [B] stays the same), and the rate doubles as well. So, 2 = 2^n, n being the order of A; in this case, A is first order and n=1.

3.) For the order of B, lets look at experiments 2 and 3. While [A] stays the same, [B] is doubled. Meanwhile, the rate is multiplied by 4 (47.9/11.9=4). So, we get 4 = 2^m, m being the order of B; in this case, B is second order and m=2.

4.) As for rate law, fill in your generic rate law rate=k[A]^n[B]^m[C]^l using what we just found for n, m, and l.

5.) For the rate constant, fill in the rate law you get in the previous step with data from one of the experiments. Solve to find k.

[Bethany Yang 2E]

Hey!

1.) So, we can start first by determining the order for C in the rate law. Since we don't see C remain constant in two rxns, we can infer that it does not affect the rate of the rxn. For C, l=0.

2.) Then, we can look at A. Dr. Lavelle explained the sure-fire way to determine the order of species in lecture by using two lines of the table for rate=k[A]^n[B]^m[C]^l, but we can also do it as I'm about to explain, which is a little quicker than writing everything out. If you look at experiments 1 and 2, the concentration of A doubles (while [B] stays the same), and the rate doubles as well. So, 2 = 2^n, n being the order of A; in this case, A is first order and n=1.

3.) For the order of B, lets look at experiments 2 and 3. While [A] stays the same, [B] is doubled. Meanwhile, the rate is multiplied by 4 (47.9/11.9=4). So, we get 4 = 2^m, m being the order of B; in this case, B is second order and m=2.

4.) As for rate law, fill in your generic rate law rate=k[A]^n[B]^m[C]^l using what we just found for n, m, and l.

5.) For the rate constant, fill in the rate law you get in the previous step with data from one of the experiments. Solve to find k.

Thank you for taking the time to write this out! This helped a lot :)

[Aliya 1H]

Hey!

1.) So, we can start first by determining the order for C in the rate law. Since we don't see C remain constant in two rxns, we can infer that it does not affect the rate of the rxn. For C, l=0.

2.) Then, we can look at A. Dr. Lavelle explained the sure-fire way to determine the order of species in lecture by using two lines of the table for rate=k[A]^n[B]^m[C]^l, but we can also do it as I'm about to explain, which is a little quicker than writing everything out. If you look at experiments 1 and 2, the concentration of A doubles (while [B] stays the same), and the rate doubles as well. So, 2 = 2^n, n being the order of A; in this case, A is first order and n=1.

3.) For the order of B, lets look at experiments 2 and 3. While [A] stays the same, [B] is doubled. Meanwhile, the rate is multiplied by 4 (47.9/11.9=4). So, we get 4 = 2^m, m being the order of B; in this case, B is second order and m=2.

4.) As for rate law, fill in your generic rate law rate=k[A]^n[B]^m[C]^l using what we just found for n, m, and l.

5.) For the rate constant, fill in the rate law you get in the previous step with data from one of the experiments. Solve to find k.

Thank you for taking the time to write this out! This helped a lot :)

ofc! glad i could help :)