ns 120 Unit 3Module 3Inside cloud warms from latent heat of condensationWater is the only substance on Earth that cycles through its solid liquid and gaseous phases at the typical temperatures found on the planet. A significant heat exchange occurs between a molecule of H2O and the environment during each phase change. To understand this fully let’s first point out a significant feature of the metric system of measurements. The system is partially based on dimensional relationships with the most important compound on the planet: water.For this discussion mass is measured in grams length is in centimeters volume is in centiliters temperature in degrees Celsius (C) and heat in calories. One gram of water has a size of one cubic centimeter and a volume of one centiliter. The amount of heat required to raise one gram water by one degree C specifically from 14.5 to 15.5 degrees C is one calorie. The use of a temperature value around 15 C is significant because 15 C is approximately the average global surface temperature on Earth.Conversion between different phases of H2O requires an exchange of heat between the H20 molecule undergoing the change of state and the environment. During melting of ice sublimation of ice and evaporation of water the environment loses heat. During condensation of water vapor deposition of water vapor and freezing of water the environment gains heat. Meteorology calls this heat exchange latent heat. You were introduced to this term in Module 2.Instructions for this Discussion ActivityFor this discussion activity respond to the following prompts:Provide a very simple example in which you personally have experienced heat loss (feeling colder) during evaporation of water from your body.Next find from the text or the Internet the numerical amount of heat required to evaporate one gram of water at normal surface temperatures on the earth.Explain how this value compares and contrasts with the amount of heat (one calorie) needed to change the temperature of one gram of water by one degree C.Does the difference in magnitude surprise you? Explain why or why not.Discuss the implications of your findings on these two values. Consider the development of clouds and think about its impact on the formation and maintenance of thunderstorms. Use the concepts of stability and instability.Once you have posted your own discussion response you are required to comment substantially on the posts of at least two of your classmates. You can agree or disagree with their posts but you must explain why you have chosen to do so. Remember if you provide a quote or information from a source (e.g. your textbook or the Internet) you must include the correct citation and reference in APA style.
