Why is vapour pressure of a liquid not measured steadily in an open vessel?
Answer and explanation
Correct answer: Because vapour keeps escaping
In an open vessel, molecules that evaporate disperse into the surrounding atmosphere instead of accumulating above the liquid. A stable liquid-vapour equilibrium and a definite equilibrium pressure therefore cannot be maintained in the usual sense. A closed vessel allows evaporation and condensation to balance. Vapour does form in an open vessel; it simply escapes continuously.
Frequently asked questions
What is the correct answer to this question?
Because vapour keeps escaping
Why is this the correct answer?
In an open vessel, molecules that evaporate disperse into the surrounding atmosphere instead of accumulating above the liquid. A stable liquid-vapour equilibrium and a definite equilibrium pressure therefore cannot be maintained in the usual sense. A closed vessel allows evaporation and condensation to balance. Vapour does form in an open vessel; it simply escapes continuously.
Which subject and chapter does this question cover?
This is a Class 11 Chemistry question. Chapter: Equilibrium. Topic: Equilibrium in physical and chemical processes.
