MATHEMATICS · Multi-part · AP · Calculus AB · Differential Equations · Differential Equations
Problem
In a chemical reactor, the concentration C(t) of an impurity (in mol/L) satisfies
dtdC=−0.3C(5−C),t≥0,
where t is measured in minutes.
(a) Identify all constant (equilibrium) concentrations predicted by the model.
(b) For C(0)=2, determine the sign of dtdC at t=0 and describe the long–term behavior of C(t) as t→∞.
(c) For C(0)=8, determine the sign of dtdC at t=0 and describe the long–term behavior of C(t) as t→∞.
(d) Sketch qualitative solution curves for initial concentrations both below and above the equilibria, labeling arrows to indicate the direction of change over time.