![]() ![]() See Water and Heavy Water - thermodynamic properties. ![]() Note! Temperature must be within the ranges 0-370 ☌, 32-700 ☏, 273-645 K and 492-1160 °R to get valid values. The output specific heat is given as kJ/(kmol*K), kJ/(kg*K), kWh/(kg*K), kcal/(kg K), Btu(IT)/(mol*°R) and Btu(IT)/(lb m *°R) The calculator below can be used to calculate the liquid water specific heat at constant volume or constant pressure and given temperatures. Isobaric specific heat (C p ) for water in a constant pressure (ΔP = 0) system.I sochoric specific heat (C v ) for water in a constant-volume, (= isovolumetric or isometric ) closed system.The specific heat is given at varying temperatures (☌ and ☏) and at water saturation pressure (which for practical use, gives the same result as atmospheric pressure at temperatures < 100 ☌ (212☏)). When calculating mass and volume flow in a water heating systems at higher temperature - the specific heat should be corrected according the figures and tables below. The less-dense hot water floats on the more dense room temperature water.Specific heat (C) is the amount of heat required to change the temperature of a mass unit of a substance by one degree. How does this help explain why hot water floats on room temperature water?.Students should realize that increasing the volume without increasing the mass is going to decrease the density. What does this tell you about the density of hot water?īased on the animation, students should understand that the spreading apart of the molecules increases the volume but does not affect the mass of the water. Hot water takes up more volume, but the mass stays the same. In the animation, you saw that as water is heated the water level rises.Make sure students notice that when the water is heated, the water level rises slightly in the graduated cylinder. Point out that the molecules in the hot water are moving faster and are a little farther apart than the molecules in room temperature water. The more dense cold water sinks in the room temperature water. How does this help explain why cold water sinks in room temperature water?.Students should realize that decreasing the volume without increasing the mass is going to increase the density. But the mass of the water does not change. Students should understand that when the molecules come together as the water is cooled, the volume decreases. What does this tell you about the density of cold water? Cold water has a smaller volume, but the mass stays the same. In the animation, you saw that as water is cooled the water level goes down.Also point out that when the water is cooled, the water level falls slightly in the graduated cylinder. Point out that the molecules of cold water move slower and are a little closer together than the hot or room temperature water. When the cold water is placed on top, the colors mix because the cold water is more dense and sinks in the hot water. Why do you think the hot and cold water mixed when the cold water was placed on top?.The water will quickly become green throughout. The cold blue water will immediately fall into the hot yellow water causing mixing. Use the same procedure as above, but place the jar of cold water, upside down over the jar of hot water.What might happen if you placed the cold blue water on top of the hot yellow water and then removed the card.Hot water is less dense so it floats on the denser cold water. Students should realize that there is a density difference between hot and cold water. Why do you think the hot water stayed on top of the cold water?.Although removing the card may result in a little mixing or spilling, the hot yellow water will remain in the top jar and the cold blue water will remain in the bottom jar. ![]()
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