text: A mass balance can also be taken differentially. The concept is the same as for a large mass balance, but it is performed in the context of a limiting system (for example, one can consider the limiting case in time or, more commonly, volume). A differential mass balance is used to generate differential equations that can provide an effective tool for modelling and understanding the target system.
  The differential mass balance is usually solved in two steps: first, a set of governing differential equations must be obtained, and then these equations must be solved, either analytically or, for less tractable problems, numerically.
  The following systems are good examples of the applications of the differential mass balance:
  # Ideal (stirred) batch reactor
  # Ideal tank reactor, also named Continuous Stirred Tank Reactor (CSTR)
  # Ideal Plug Flow Reactor (PFR)