A $500$ m$3$ reactor is filled with clean water. At t $=0,$

the pump is turned on$,$ pumping in a salt solution

having a concentration of $100$ mg$/$L at a flowrate of $50$

m$3/$day $($approximately $0\mathrm{.}6$ L$/$s$).$ The volume of solution

in the reactor is constant.

$$ Draw a picture of the system, showing the control volume,

system boundary, flows in and out of the reactor.

$$ State your assumptions.

$$ Write a mass balance equation in words.

$$ Write the mass balance equation using mathematic terms.

$$ Draw a graph showing how you expect the concentration in

the reactor to vary with time