Period+1+Group+6

Response to Investigation 6 Essential Question(s)**
 * Period 1 Group 6

=We can determine that there is water vapor in the air by doing an experiment with dyed ice and a cup. It gets in the air from transpiration, respiration, and evaporation. We learned this when we were doing the cup and ice experiment. Another way is analyzing the lab when we put water on the outside of your hand and blew on it. When you place ice in a cup and you add a drop of food coloring in it, you prove that any condensation on the outside of the cup came from the air, not the inside out. Water vapor gets in the air by transpiration, when plants take in water and release it out of the leaves as water vapor, respiration, which is when terrestrial animals exhale water vapor when they breath and when water gets heated is evaporates.=
 * 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?**

=**Humidity is the amount of water vapor in the air. It is measured in percent. We learned this when we had class discussions and when we did the humidity packets. Also, when we read the article Dragon's Breath** and answered questions on humidity. Humidity is just the amount of water vapor in the air as for relative humidity is the amount of water vapor in the air compared to the amount of water vapor needed to saturate a volume of air at a given temperature. The highest percent of humidity is 100 percent. When there is a lot of water vapor in the air, it is humid. You can measure humidity by a hygrometer.=

=Dew point is the temperature at which water vapor changes from a gas to a liquid and it's measured in degrees celcius. I got this information from the dragon's breath article, the cloud article and the upper-air sounding graph. Dew point is the temperature at which air is saturated, or when the air is full,mostly with water vapor. Dew point is not the same every where. Dew point can change from day to day depending on how much water vapor is in the air. When reading the articles they told us exactly what dew point was and how it was measured. The upper-air sounding graph told us how you could measure how much water vapor was in the air, it then showed us the grams of water per kilogram of air.=

=Dew forms on a surface that is colder then the air around it. Dew forms when the air reaches dew point and then water condenses on grass, leaves, windows,etc., as dew. Dew is condensation. Clouds form when water vapor condenses onto condensation nuclei and then the nuclei combine and form a cloud. We learned this during an experiment that we did in class, we learned about how dew forms in the article "Observing Clouds". In the experiment we did in class we put a little water (about 2 inches) in the bottom of a 2 liter bottle. Then we shook the bottle to resemble the molecular motion speeding up, this also helped the air in the bottle to start to evaporate. In order for the cloud to form we added a match and that allowed the water vapor to settle on the dust particle (the dust particle resembled a nuclei in the atmosphere). We then squeeze the bottle and when released it would then form a faint cloud becasue the water vapor had something to kling on to and would then come together as a visible cloud. We learned how dew forms by the article when it said that the water vapor forms onto tiny particles and makes it visible to see. Clouds form when the sun gives off energy to make the water evaporate. When the water evaporates and rises (less dense) the water vapor will rise high into the atmosphere and become colder. Once the water vapor and air rise high enough to get cold enough, it will saturate and reach dew point. It will then condense on condensation nuclei. As the nuclei builds up it will cause a visible cloud to form. Dew forms when air reaches dew point and then water condenses onto cool surfaces. Dew is a thin layer of tiny drops of water. When water vapor comes to a cool surface, it will transfer its energy, and then it looses molecular motion. When it gets cool enough, it will transfer back into being a liquid, into being dew.=

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