QUESTION TWO In a reaction, A + B → C, data in table 3 was obtained. Determine the reaction order and the reaction rate constant for the reaction. Table 3: Experimental data Experiment no. Initial concentration of A(mol/dm3) Half life(h) 1 2 2.0 5.0 2.5 1.0

In the PhET Reactions under Options. (a) Leave the Initial Temperature at the default setting. Observe the reaction. Is the rate of reaction fast or slow? (b) Click Pause" and then Reset All, and then enter 15 molecules of A and 10 molecules of BC once again. Select Show Bonds" under Options. This time, increase the initial temperature until, on the graph, the total average energy line is completely above the potential energy curve. Describe what happens to the reaction.

A certain reaction has the form aAProducts At a particular temperature, concentration versus time data were collected. A plot of 1/ [A] versus Lime (in seconds) gave a straight line with a slope of 6.90 102. What is the differential rate law for this reaction? What is the integrated rate law for this reaction? What is the value of the rate constant for this reaction? If [A]0 for this reaction is 0.100 M, what is the first half-life (in seconds)? If the original concentration (at t = 0) is 0.100 M, what is the second half-life (in seconds)?

11.64 HBr is oxidized in the following reaction: 4 HBr(g) + O2(g) —• 2 H2O(g) + 2 Br,(g) A proposed mechanism is HBr + O2 -* HOOBr (slow) HOOBr + HBr — 2 HOBr (fast) HOBr + HBr — H2O + Bn (fast) Show that this mechanism can account for the correct stoichiometry. Identify all intermediates in this mechanism. What is the molecularity of each elementary’ step? Write the rate expression for each elementary' step. Identify the rate-determining step.

Go to the PhET Reactions and change to Angled shot to see the difference. (a) What happens when the angle of the collision is changed? (b) Explain how this is relevant to rate of reaction.

The reaction of thioacelamidc with water is shown by the equation below: CH3C(S)NH2(aq)+H2OH2S(aq)+CH3C(O)NH2(aq) The rate of reaction is given by the rate law: Rate=k[H3O+][CH3C(S)NH2] Consider one liter of solution that is 0.20 M in CH3C(S) NH2 and 0.15 M in HCl at 25C. a For each of the changes listed below, state whether the rate of reaction increases, decreases, or remains the same. Why? i. A 4-g sample of NaOH is added to the solution. ii. 500 mL of water is added to the solution b For each of the changes listed below, state whether the value of k will increase, decrease, or remain the same. Why? i. A catalyst is added to the solution. ii. The reaction is carried out at 15oC instead of 25C.

For the reaction A+BC, explain at least two ways in which the rate law could be zero order in chemical A.

The reaction 2 NO(g) + 2 H2(g) N2(g) + 2 H2O(g) was studied at 904 C, and the data in the table were collected. (a) Determine the order of the reaction for each reactant. (b) Write the rate equation for the reaction. (c) Calculate the rate constant for the reaction. (d) Find the rate of appearance of N2 at the instant when [NO] = 0.350 mol/L and [H] = 0.205 mol/L.

As with any drug, aspirin (acetylsalicylic acid) must remain in the bloodstream long enough to be effective. Assume that the removal of aspirin from the bloodstream into the urine is a lirst-order reaction, with a half-life of about 3 hours. The instructions on an aspirin bottle say to take 1 or 2 tablets every 4 hours. If a person takes 2 aspirin tablets, how much aspirin remains in the bloodstream when it is time for the second dose? (A standard tablet contains 325 mg of aspirin.)

The type of rate law for a reaction, either the differential rate law or the integrated rate law, is usually determined by which data is easiest to collect. Explain.