What is how much does a pound of water weigh?

A pound of water weighs approximately 16 ounces or 0.45 kilograms. This is equivalent to about 0.12 gallons or 0.45 liters of water. The weight of water can vary depending on its temperature and pressure. At sea level and room temperature (68°F or 20°C), water weighs 8.35 pounds per gallon or 1 gram per milliliter. However, the weight of water changes at different altitudes and temperatures. For example, at high altitudes, water may boil and evaporate more easily due to lower air pressure, which changes its weight.