Question

Which of the following statements is not true for a system that has reached the eutectic temperature?

(a) The system is a open system

(b) The system is a miscible fluid

(c) Components lie in liquid state

(d) A region between sublimation and eutectic curve lies stable

I got this question during an interview for a job.

I want to ask this question from Two Component System in section Phase Rule of Engineering Chemistry I

Answer 1

Correct answer is (a) The system is a open system

For explanation: The eutectic temperature is achieved by heating a liquid in the point where the density of the liquid state is equal to the density of the vapor state. Here, the interface between the liquid and vapor vanishes resulting in a miscible fluid. This can only occur in a closed system (otherwise the vapor would escape into the surroundings).