Ammonia gas $($A$)$ is diffusing through a uniform tube $0\mathrm{.}10$ m long containing N$2$ gas $($B$)$ at $1\mathrm{.}0132$ x$105$ Pa pressure and $298$ K$.$

At point $1,$ pA$1=1\mathrm{.}013$x$104$ Pa$,$ and at point $2,$ pA$2=0\mathrm{.}507$ x$104$ Pa$.$ the diffusivity DAB $=0\mathrm{.}230$ x$10-4$ m$2/$s$.$

a$)$ specify the sink and the source

b$)$ make a list of assumptions

c$)$ derive the general differential equation

d$)$ calculate the flux of A and B