Question I

The distributed paranteter model of mass transfer analysis can be used to evaluate concentrati$$r changes with poxition and time.

A$)$ Explain the difference between the species molar fluxes J and Ni$,[4$ marks$]$

B$)$ There is bulk Ilow in equimolar counter$-$diffusion $($Yes No$)?$ Explain $[3$ marks$]$

C$)$ Methane $(A)$ diffuses at steady state through a tube conlaining helium $($B$)$ At point I the mole fraction of methanc is $0\mathrm{.}543$ and at point $2.$ which is $30mm$ apart, the mole fraction of methane is $0\mathrm{.}148.$ The total pressure is $101\mathrm{.}32$APa and the temperature is ${20}^{6}C.$ At this pressure and temperature the mutual diffusivity is $6\mathrm{.}75{10}^{-5}\frac{m^2}{s}.$ Show your work clearly and:

i$)$ Caleulate the steady state molar flux of methane for equimolal counter diffusion $[6$ marks$]$

ii$)$ Under conditions of $Q3($i$)$ above, calculated the partial pressure of methane at $2cm$ from point $1[3$ marks$]$

iii$)$ Under conditions of $3($i$)$ abowe, calculate the molar flux of methane at $25C$