Benzenediazonium chloride decomposes by a first-order reaction in water, yielding N₂(g) as one product. 

The reaction can be followed by measuring the volume of N₂(g) as a function of time. The data in the table on the next page were obtained for the decomposition of a 0.071 M solution at 50 °C, where t = ∞ corresponds to the completed reaction.

(a) Convert the information given here into a table with one column for time and the other for [C₆H₅N₂Cl].

(b) Construct a table similar to Table 20.2, in which the time interval is Δt = 3 min.

(c) Plot graphs similar to Figure 20-2, showing both the formation of N₂(g) and the disappearance of C₆H₅N₂Cl as a function of time.

(d) From the graph of part (c), determine the rate of reaction at t = 21 min, and compare your result with the reported value of 1.1 x 10^-3 M min^-1.

(e) Determine the initial rate of reaction.

(f) Write the rate law for the first-order decomposition of C₆H₅N₂Cl, and estimate a value of k based on the rate determined in parts (d) and (e).

(g) Determine t_1/2 for the reaction by estimation from the graph of the rate data and by calculation.

(h) At what time would the decomposition of the sample be three-fourths complete?

(i) Plot ln[C₆H₅N₂Cl] versus time, and show that the reaction is indeed first order.

(j) Determine k from the slope of the graph of part (i).

Transcribed Image Text:

C6H5N₂Cl(aq) →→→ C₂H₂Cl(aq) + N₂(g)