Question

Nitrosyl bromide decomposes by the reaction 2 NOBO(g) + 2NO(9) + Brz(9). Show that the following data are consistent with a second-order reaction and determine the second-order rate constant for the reaction. Students may do this by plotting the data three different ways. For each plot, time goes on the x-axis. A zero-order reaction is linear when [NOBr] on the y-axis. A first-order reaction is linear when In[NOBr) is on the y-axis. A second-order reaction is linear when 1/[NOBr) is on the y-axis. 5 10 15 30 [NOBr] 0.0653 0.0514 0.0424 0.0361 0.0249 5 45 0.0190 M chemPad x.x" - Help Greek What is the rate law for the reaction? (Rate equations take the general form 'rate = k. [A] [B]'.) What is the value of the rate constant at the temperature of the experiment? 0.829 X What are the units for the rate law? M-3.5-1 OM-2.5-1 om-2.5-2 OM-1.5-1

Answer 1

solution Criven C Data of concentration of No Br with time has been given, so we plot [NoBrĮ verses time for zeno arden check. → But plot is not linear, it is curre. So reaction is not Zeno orden → Then we plotted In [No Br But plot is not linear. ] verses time for first orden check. not Then we plafted verses time this olot give us JOB linear line Therefore reaction is second orden 80 Rate law for reaction rate = k [No Br? Here ka rate constant - d[NOBY] k[ Noor] ? dt * {& ENOBY] = (ket (NOB] 2 ) - te = kt te (NOBY] y = ma te >

When we plot 1 verses t, and NOBY compare with equation of - line of rate constant Slop of this line gives us value al tro, Cwo Br] = 15.3139 at tals were = 27.40083 - 27. 33 & Slope = (27.70083 – 15.3139) (15 - 0) Slope K = 0.82579] Mis - unit of rate law rate = = k[ No Br] ² [M74 M.s a 1 = M si unit of rate law since there is no option like this that means in the question unit of rate constant has been asked instead of rate 0) MS! unit of rate second order constant.

Time 0.0000 5.0000 10.0000 15.0000 30.0000 45.0000 [NOBr] 0.0653 0.0514 0.0424 0.0361 0.0249 0.0190 Ln[NOBr] -2.7288 -2.9681 -3.1606 -3.3215 -3.6929 -3.9633 1/[NOBr] 15.3139 19.4553 23.5849 27.7008 40.1606 52.6316

[NOBr] verses Time (for zero order check) 0.07 0 0.053 [NOBY] 0.035 0 0.018 O 0 5 12. 12.5 25 2 5 Time t (in seconds) 37.5 50

In[NOBr] verses Time (for first order check) Ln(NOB) 12.5 37.5 Time t (in seconds)

1/[NOBr] verses Time (for second order check) 1/(NOB) 12.5 37.5 25 Time t (in seconds)