Question

________ Rule is often used to compare a pure liquid and a solution at a given concentration.

(a) Duhring’s rule

(b) Plank rule

(c) Friction rule

(d) Doppler rule

The question was posed to me in a job interview.

The origin of the question is Evaporator in chapter Building Blocks of Dairy Processing of Dairy Engineering

Answer 1

Right choice is (a) Duhring’s rule

The best explanation: Duhring’s rule states that a linear relationship exists between the temperatures at which two solutions exert the same vapour pressure. The rule is mostly used to compare a pure liquid and a solution at a given concentration.