The temperature at which water boils is directly influenced by which parameter?

The temperature at which water boils is primarily influenced by altitude due to atmospheric pressure changes. At sea level, where atmospheric pressure is highest, water boils at 100 degrees Celsius (212 degrees Fahrenheit). However, as altitude increases, atmospheric pressure decreases, leading to a lower boiling point for water. For instance, at higher elevations, such as in mountainous regions, water may boil at temperatures well below 100 degrees Celsius. This phenomenon occurs because the reduction in pressure allows water molecules to escape into the vapor phase more easily, requiring less thermal energy to reach the boiling point.

Color, humidity, and volume of water do not have a significant direct effect on the boiling temperature of water. While humidity can influence other factors such as heat transfer and specific heat, it does not alter the boiling point directly. Similarly, the color of the water or the volume present does not change the fundamental physical property of boiling point, which is primarily determined by pressure. Therefore, altitude is the correct and relevant parameter that directly impacts the temperature at which water boils.