High School

What is the vapor pressure of ethanol at [tex]90^{\circ} C[/tex]?

A) 40 kPa
B) 101.3 kPa
C) 55 kPa
D) 150 kPa

Answer :

To determine the vapor pressure of ethanol at [tex]\(90^\circ C\)[/tex], we rely on standard scientific data known about the behavior of ethanol under these conditions.

At a temperature of [tex]\(90^\circ C\)[/tex], the vapor pressure of ethanol is well-documented. Among the multiple-choice options provided:

A) 40 kPa
B) 101.3 kPa
C) 55 kPa
D) 150 kPa

The correct vapor pressure of ethanol at [tex]\(90^\circ C\)[/tex] is 55 kPa. Therefore, the correct answer is option C) 55 kPa.

Understanding vapor pressure involves recognizing that it represents the pressure exerted by a vapor in equilibrium with its liquid at a given temperature. For ethanol, as the temperature increases, so does its vapor pressure, due to the increased energy allowing more ethanol molecules to escape into the vapor phase.

In conclusion, at [tex]\(90^\circ C\)[/tex], ethanol's vapor pressure is 55 kPa.