Period+3+Group+4

Response to Investigation 6 Essential Question(s)**
 * Period 3 Group 4

=We can determine that water vapor is in the air by condensing the water vapor in the air on to a cold surface. We learned this when we did this as an experiment in class. The cold water in the cup absorbed the heat from the water vapor surrounding the cup and the water vapor lost enough heat (energy and molecular motion) to turn back to a liquid. The liquid formed on the side of the cup and we can prove that this actually was water vapor because the water in the cup was a different color and there was plastic wrap on the opening of the cup so there was no way water could have come out. Water vapor gets in our air by evaporation. We learned this from the demonstration in class where we dipped our fingers in water and made a circle with it on the top of our hand. When the liquid water heated up, it evaporated and turned from a liquid to water vapor which is water's gas form. The water heated up because the heat in our hand transferred to the water on our hand. The particles of the water increased in molecular motion due to conduction of the heat from our hand to the water allowing it to evaporate into the air. Humidity is the amount of water vapor in the air and is measured in percent by a hygrometer. I know this from investigation one when we used the hygrometer that measured humidity while we went outside and measured the visibility, humidity, and the dew point with the weather tools. It was measured in percent, the percent comparing the humidity in the air at the time of the reading to the total amount of water vapor the air could have held. Dew point is the temperature at which air is saturated and watervapor turns back to a liquid. It is measured in degrees Celsius. I know this from the Dragon’s Breath article that explained relative humidity and dew point. In the article it explains that when a certain volume of air is fully saturated with water vapor, that teperature at which the air is saturated is dew point. Clouds form when water vapor in the air attaches onto a condensation nuclei, a surface where water vapor condenses in the atmosphere. Condensation nuclei can be anything from dirt to pollen to dust. Dew is formed in a similar war. Water vapor condenses to a colder surface such as grass. I know this because of our bottle demonstration where we saw it when you added ice.=
 * How can we determine that water vapor is in the air and how does it get there? What is humidity and what is dew point and how are each measured? How do clouds and dew form?**