Page 538 - Modelling in Transport Phenomena A Conceptual Approach
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518                    APPENDIX  A.  MATHEMATICAL PRELIM2NARIES


            The value of  the integral can be  calculated from Eq.  (A.8-9) as

               0 = 100 I19.65 + 2(26.74 + 32.80 + 37.74 + 41.75 + 45.06 + 47.83) + 50.161
                     2
                 = 26,683 cal/ mol

            Simpson’s rule with n = 4
            From Eq.  (A.8-12)
                                           1000 - 300 = 175
                                     AT  =
                                               4
             Therefore, the values of  cp  at  5 equally spaced points are given in the following
             table:

                T          CP
               ( K)    ( cal/ mol. K)
              ~
               300        19.65
               475        31.50
               650        39.50
               825        45.75
               1000       50.16

             The value of  the integral using Eq.  (A.8-11) aS

                         Q=-- 175 [19.65 + 4(31.50 + 45.75) + 2(39.50) + 50.161
                              3
                           = 26,706 cal/ mol


             A.8.4  Numerical Integration When the Integrand is a
                      Continuous Function

             A.8.4.1 Gauss-Legendre quadrature
             The evaluation of an integral given by Eq. (A.&l), where a and b are arbitrary but
             finite, using the Gauss-Legendre quadrature requires the following transformation:
                                      x= (?>..-       a+b

                                                       2                     (A.8-13)
             Then Eq. (A.8-1) becomes






                                                                             (A.8-14)
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