Lesson Plan of Evaporation and Condensation
General Science Grade V
Students’ Learning Outcomes
· Describe the role of evaporation and condensation in the water cycle.
· Identify and describe forms of moisture in the environment.
(e. g. dew, snow, fog, frost and rain)
Information for Teachers
· When a liquid like water is kept in an open container, its particles continuously move from liquid phase to air. This process is called evaporation and it continues at all temperatures.
· During night when the temperature of air falls, the water vapours present in air get together and form droplets of water. The process is called condensation.
· It forms when the temperature of an object drops below the dew point temperature. … Frost: the ice crystals formed by deposition of water vapor on a relatively cold … over marshy areas or soil saturated by a recent heavy rainfall or rapid snowmelt. … humid air flows over relatively cold, snow-covered ground in early spring, …
Material / Resources
Plastic bowl, water, ice, stainless steel glass, textbook
Worm up Activity
Ask the students:
· You must have seen your mother spreading laundry in the open air. After some time the clothes get dry. Where does the water go from the wet clothes? ( Students’ response: it evaporates in the presence of sunlight)
· Ask students have you been to a nearby garden early in the morning. Why does the grass feel wet? (Students’ response: The grass is wet due to early morning dew)
· Draw this diagram on the board and explain both the processes.
· Take water in a bowl. Draw a line in the bowl to indicate the level of water.
· Ask a student to keep the bowl in the sunlight.
· After some time ask the student to bring the bowl back in the classroom.
· Let all the students observe the level of water in the pond.
· Ask the students the following questions:
—–What change has occurred in the level of water in the bowl?
( Students’ response: It has lowered)
——Where does the water from bowl go?
(Students’ response: It has changed into Vapours due to heat of the Sun)
· Explain that small drops in the air are called water vapours. They are not visible.
· Take a stainless steel glass wipe its outer surface with dry cloth. Add some ice cubes into it.
· After some time let the students observe the outer surface of the glass.
—–What has appeared on the outer surface of glass?
(Students’ response: Small droplets of water appear on the outer surface of glass.)
——Where these droplets have come from?
(Students’ response: Water vapours present in air, on touching the cold surface of glass,
get together to form droplets. This process is called condensation)
· Teacher will inform the students that when water vapours reach upper atmosphere they condense due to low temperature and form clouds. Clouds cause rain.
· Ask students to name the main sources of water in the world?
(Students response: Sea, Lakes, Rivers, Ponds, Oceans & atmosphere.
· Inform students that all these reservoirs are called water bodies.
Water moves continuously through each of the water bodies by the processes of evaporation and condensation and the phenomenon is called water cycle.
· The transfer of water mainly from oceans and other water bodies to the atmosphere takes place through evaporation. Most water vapours return to the oceans, while some vapours are carried by wind to different areas of land.
· Here the vapours condense due to low temperature and fall back on earth in the form of rain, snow and hail and sometimes in the form of dew and fog.
· During winter when the morning temperature is very low, drops of water condense and suspend in the atmosphere as fog.
· In intense cold days these water droplets fall down as frost. This is the way nature distributes water throughout the land for our daily use.
Sum up / Conclusion
· Water moves continuously through different water bodies present on the earth by the processes of the evaporation and condensation and the phenomenon is called water cycle.
· Early in the morning and at night water vapours condense together to form droplets and come down on earth as dew or suspend in the atmosphere as fog. This process is called condensation.
· Ask students the following questions:
—How clouds are formed?
(Students response: Water vapours coming from ocean rise up in the cooler portion of the
Atmosphere. Here they condense to form clouds)
—What is the difference between rain and dew?
(Students response: Water vapours present in clouds condense together due to low temperature at high altitude).
· Under favorable condition this condensation causes water to precipitate as rain. At night or early in the morning water vapours present in air condense together to form small droplets. These droplets then fall down as dew)
—-How is water present in oceans distributed throughout the land on earth?
( Students response: Wind carries vapours present above the oceans to far off places on earth,
where they get together at cooler places to form clouds. These clouds then cause rain and
water is distributed throughout the land on earth)
· Involve the students in solving the questions given at the end of chapter / unit of textbook,
Ask the students to write answer to the following questions:
—–While taking a bath during winter with hot water what do you observe in a bathroom?
(Students response: During bath hot water evaporate to form fog in the bath room)
—–At which times, there is maximum possibility of the formation of dew or fog.
(Students response: Early in the morning or during night the temperature of the
As fog. Alternatively heavy droplets of water fall down in the form of dew)
——What is the name of the process in which water vapours are converted into liquid water ?
(Students’ response: condensation)