Question

O KINETICS AND EQUILIBRIUM Deducing a rate law from the change in concentration over time A chemistry graduate student is studying the rate of this reaction: 2H, PO, (aq) — P,0, (aq) +3H ,0 (aq) She fills a reaction vessel with H, PO, and measures its concentration as the reaction proceeds: time [H,PO] (milliseconds) 0.600 M 10. 0.389 M 20. 0.252 M 30. 0.163 M 40. 0.106 M Use this data to answer the following questions. Write the rate law for this reaction. rate = k 0.0 Calculate the value of the rate constant k. k = | Round your answer to 2 significant digits. Also be sure your answer has the correct unit symbol.

Answer 1

if A= H3PO4 Time in concentration in milliseconds M H3PO4 [A] 0.6000 0.3890 In[ H3PO4 1 1/1 H3PO4 1 In[A] 1/[A] -0.511 1.667 answer: a Order of the reaction is 1 because the strait line is obtained in the graph with In[A] Vs time because the strait line is obtained in the graph with In[ H3PO4 ] Vs time rate = k [ H3PO4 ] answer: b rate constant k = [In([A]o /[A]t)]/t rate constant k = _ 1 in 0.6000, 10 Inl 2000) rate constant k = 0.043 msec-1 rate constant k = 0.043 ms -1 10 -0.944 2.571 20 0.2520 3.968 -1.378 -1.814 30 0.1630 6.135 40 0.1060 -2.244 9.434 [H3PO4] In[H3PO4] 1/[H3PO4) 0.7000 0.6000 0 10 20 30 40 50 0.5000 0.4000 0.3000 0.2000 0.1000 0.0000 0 10 20 30 40 50 - 10 20 30 40 50