In terms of vaporization, at what temperature does water vaporize at 28 inches of Hg vacuum?

At 28 inches of mercury (Hg) vacuum, the pressure is significantly lower than standard atmospheric pressure. Water normally boils at 212°F at sea level due to the higher pressure. However, as pressure decreases, the boiling point also decreases.

At a vacuum of 28 inches of Hg, which is approximately 0.93 psi, water boils at a lower temperature than 212°F. In fact, under these conditions, water starts to boil around 10°F. This phenomenon occurs because boiling is the process where the vapor pressure of the liquid equals the surrounding pressure; with the lower pressure in the vacuum, it takes less thermal energy to reach that point.

Thus, the correct temperature at which water vaporizes in a vacuum of 28 inches of Hg is approximately 10°F. Understanding the relationship between pressure and boiling point is crucial in scenarios involving vacuum systems, as it directly affects the temperatures at which liquids change to gas.