Question

In Purdue's Chemistry department, the chemists have found that in a water based solution containing 24 grams of certain undissolved chemicals, the rate of change of the amount of chemicals dissolved in the solution is proportional to the amount of the undissolved chemicals. Let Q(t) (in grams) be the amount of dissolved chemicals at time t and let k be the positive proportionality constant. The differential equation describing the given situation is:

Answer 1

if there are Q grams of dissolved chemicals, then there are 24-Q undissolved. So,

dQ/dt = k(24-Q)

Note that the question was kind of loosely worded.