The following reactions take place in a batch reactor:

A + B ( C (desired product)

B + C ( D (hazardous product)

As the reaction proceeds, D builds up in the reactor and could cause an explosion if its concentration exceeds 15 mol/L. To ensure the safety of the plant personnel, the reaction is quenched (e.g., by cooling the reactor contents to a low temperature) and the products are extracted when the concentration of D reaches 10mol/L.

The concentration of C is measured in real-time, and samples are periodically taken and analyzed to determine the concentration of D. The data are shown below:

Cc (mol/L) ___________________ Cd (mol/L)

2.8 ......................................... 1.4

10 .........................................2.27

20 .........................................2.95

40 .........................................3.84

70 .........................................4.74

110 ........................................5.63

160 .........................................6.49

220.........................................7.32

(a) What would be the general form of an expression for CD as a function of Cc?

(b) Derive the expression.

(c) At what concentration of C is the reactor stopped?

(d) Someone proposed not stopping the reaction until CD = 13 mol/L, and someone else strongly objected. What would be the major arguments for and against that proposal?