How does pressure influence the boiling point of a substance?

The boiling point of a substance is the temperature at which its vapor pressure equals the external pressure surrounding it. When pressure increases, the vapor pressure must also rise in order for the substance to boil. Since higher pressure requires the substance to reach a higher temperature to achieve this vapor pressure, the boiling point consequently increases.

This relationship is governed by the physical principles surrounding phase changes and vaporization. For instance, in a high-altitude environment, where atmospheric pressure is lower, water boils at a temperature lower than 100°C. Conversely, in a pressure cooker, where the pressure is higher than atmospheric pressure, water can reach temperatures above 100°C before boiling occurs.

Understanding this concept is vital in various scientific and engineering applications, including cooking, chemical reactions, and the design of pressure vessels. Thus, the correct answer accurately reflects the fundamental principles of thermodynamics regarding how pressure affects the boiling point of substances.