Question

Which of the following best describes what happens to the substance between t4 and t5?

(A) The molecules are leaving the liquid phase.
(B) The solid and liquid phases coexist in the equilibrium.
(C) The vapor pressure of the substance is decreasing.
(D) The average intermolecular distance is decreasing.
(E) The temperature of the substance is increasing.

Answer 1

Between the temperature points
`t_(4)` and
`t_(5)`, the molecules are leaving the liquid phase.

Step-by-step explanation:

Reading the conversion of states of matter through a graphical representation; we can easily see that the matter is converting from the liquid phase to gaseous phase respective to the temperatures
`t_(4)` to
`t_(5)`.

As the solid is heated at a constant rate at 1 atm pressure, it changes its state from solid to liquid and then liquid to gas consistently.

As the matter crosses the temperature
`t_(4)`, it leaves it's liquid phase and starts transforming into its gaseous version. It's quite obvious that the temperature will go on increasing until the matter reaches its gaseous state.