Period+2+Group+1

Response to Investigation 6 Essential Question(s)**
 * Period 2 Group 1


 * 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?**

=We can determine that water vapor is in the air through condensation, by taking it out, and it gets there through evaporation. We learned this in the 'Dragon's Breath' article, the Water in the Air lab, the Hand/Water Evaporation lab, and the Wet and Dry Bulb Thermometer lab. We can determine that there is water vapor in the air by taking it out. For instance, when we put ice cold water, dyed, in a cup, the heat began to transfer from the air to the cup. The cooler air molecules condensed onto the cup, creating condensation. Condensation is when a gas form of water(water vapor)turns back into liquid water. The dye in the water showed that the condensation came from the air, not the cup, because it was clear. Water vapor gets into the air through evaporation. After the energy in absorbed into the water from the sun, increasing molecular motion, the molecules begin to move so quickly that they change from a liquid to a gas, water vapor.= = = =Humidity is the percentage of water vapor in the air at any given air temperature. It is measured by a wet and dry bulb thermometer, psychrometer, Hygrometer, and a humidity calculator to find the percentage of relative humidity. Dew point is the temperature at which the air is saturated, measured by a thermometer in degrees Celsius. We learned this in the 'Dragon's Breath' article, the Calculating Relative Humidity lab page, the Dew Point questions lab page, the Wet and Dry Bulb Thermometer lab, and the Hand/Water Evaporation lab. Humidity is the amount of water vapor in the air, which changes as the air temperature changes. Humidity is measured in percent and we used wet and dry bulb thermometers in class to measure it, like we did in the Wet and Dry Bulb Thermometer lab. Dew point is the temperature at which the air has become fully saturated with water vapor. This is measured in degrees Celsius by a thermometer.=

=Clouds form when water vapor condenses onto condensation nuclei. Dew forms when the temperatures of a surface, grass, window, etc, is lower than the air around it so the water vapor condenses. We learned this from when we made the Cloud-In-A-Bottle in class, read 'Dragon's Breath' article, 'Observing Clouds' article, and the Water in the Air lab. When an energy source, (the sun), transfers its energy to a water source the water molecules gain molecular motion and start to speed up, transferring into the gas stage, known as water vapor. When they change into water vapor they evaporate into the air and rise because they became less dense. When the air becomes saturated and reaches dew point, the temperature at which the air is saturated, the air temperature cools and the water vapor condenses onto condensation nuclei, salt, dust, and smoke particles, and after billions of condensation nuclei group together they form a visible cloud. Dew forms when the air is warmer than the surrounding air so it falls, being less dense, and when it reaches the cooler surfaces transfers its energy and condenses as liquid water.=