# Chemistry

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So, I go to high school in Texas and we have this AP Chem lab due online tomorrow night by midnight and I need some serious help on these questions:
Lab Temp 0.2°C
Experiment Trial Time in seconds Trial 1 Trial 2 Average Time
1 1 2 256 275 268
2 1 2 215 226 220.5
3 1 2 83 59 71
4 Temp here is 35 ° C 1 83 Unnecessary

Initial concentrations: Experiment [S203^2-] [S208^2-] [I-]
1 .0022 .0044 .2222
2 .0022 .0088 .2222
3 .0022 .0044 .4444
Initial rates from experiments 1,2, and 3 from [S2O3^2-] / ∆t: Experiment [Na2S2O3] (M) Avg. Elapsed Time (s) ∆ Na2S203/ ∆t (M/s) ∆ S208^2-/ ∆ t (M/s)
1 .0022 268 8.2X10^-6 4.10*10^-6
2 .0022 220.5 9.97X10^-6 4.98X10^-9
3 .0022 71 3.10X10^-5 1.55X10^-5

Questions:

1. Determine the reaction orders to S2O8^2- using experiment 1 and experiment 2. Hint: Use m = log (rate 1/rate 2) divided by log (concentration 1/ concentration 2).

2. Determine the reaction orders to I- using experiment 1 with experiment 3. Hint: Use n = log (rate 1/rate 3) divided by log (concentration 1/ concentration 3).

3. What is the calculated rate law for this equation/reaction? Considering most rate orders have whole integers, what is most likely the correct rate law for this reaction?

4. Using the reaction rate calculated, calculate the rate constant for experiments 1, 2, and 3, and then the average rate constant for the three experiments.

5. Calculate the rate constant for experiment 4 at the elevated temperature.

6. Why are some reactions heated in laboratories?