1. UNIT 6: AIR AND WATER MEANS OF TRANSPORT By biplane By aircraft By sailboat By hot air balloonBy rocket By helicopterBy àirship By hydroplane AIR is invisible, but we can see it moving. AIR is made of different gases: Oxygen, nitrogen, carbon dioxide, water vapour and others. Plants and humans need air to survive. The strength of the air can produce electricity: A HURRICANE WIND A BREEZE A TWISTER WINDMILLS AIR AIR AIR ATMOSPHERE AIR POLLUTION The ATMOSPHERE is the air surrounding the Earth. The ATMOSPHERE protects us from the rays of the Sun. There are four main layers: 1.The troposphere: there is oxygen to breathe, but high up in the mountains there is lessso it´s hard to breathe. 2.The stratosphere 3.The Mesosphere 4.The thermosphere We have to look after the Earth because if we destroy it we will not have any protection.

2. MEANS OF TRANSPORT By boat By waverunner By canoe By raft By ferry By submarineBy ship WATER is invisible or colored by the substances contained in it. (Seaweed, bacteries, plancton…) WATER is made of different components: Hydrogen and oxygen. We cannot live without water. No human body can resist for more than 3 days. The strength of the WATER can produce electricity. The natural force of the water can be shown on : tsunamis geisers swirling water WATER WATER WATER Pure water is colorless, odorless, and tasteless HYDROSPHERE anything containing water, is a part of the hydrosphere. That water may be at the bottom of the ocean or in the top layers of the atmosphere; it is all a part of the hydrosphere. Water is in the air, on the land, between the rocks, and in every living thing. Water, in its purest form, is H 2 0 (two hydrogen atoms and one oxygen atom). Liquid water is the most important source of water as the Earth has a very nice temperature. There are sea, oceans, lakes, tributary rivers, underground water, rain… Water vapor can be found in the clouds, in the air… Water evaporates in its cycle and becomes a gas with high temperatures. Solid water can be foudn in the deep glaciers, hailing, snow, frost… when low temperature (oºC) make sliquids become solid. Drinking water The world's supply of fresh water is running out. Already one person in five has no access to safe drinking water. Dirty water can produce diarrhea, parasites… and death. Purifying plants clean the water to make it drinking water. Most of the water in the Earth is salt water, and we cannot drink it.

3. There are six important processes that make up the water cycle. 1.Condensation - the opposite of evaporation. Condensation occurs when a gas is changed into a liquid. 2.Infiltration - Infiltration is an important process where rain water soaks into the ground, through the soil and underlying rock layers. 3.Runoff - Much of the water that returns to Earth as precipitation runs off the surface of the land, and flows down hill into streams, rivers, ponds and lakes. 4.Evaporation - the process where a liquid, in this case water, changes from its liquid state to a gaseous state. 5.Precipitation - When the temperature and atmospheric pressure are right, the small droplets of water in clouds form larger droplets and precipitation occurs. The raindrops fall to Earth. 6.Transpiration - As plants absorb water from the soil, the water moves from the roots through the stems to the leaves. Once the water reaches the leaves, some of it evaporates from the leaves, adding to the amount of water vapor in the air. This process of evaporation through plant leaves is called transpiration Water cycle processes

4. The Word Starts With this Letter HintAnswer W A substance that is very important to us. We need it to live, and it covers over two thirds of the surface of the Earth. _____________________________ OA large body of water on the surface of the earth._____________________________ EA process in which liquid water turns into water vapor (a gas)._____________________________ P In transpiration, water from these objects evaporates into the atmosphere. _____________________________ C A fluffy-looking object in the sky that contains tiny water droplets or ice particles. It is formed when water vapor condenses. _____________________________ R This type of precipitation is water that falls from clouds in a liquid state. _____________________________ S This type of precipitation is water that falls from clouds in a fluffy, frozen state. _____________________________ GA large, slowly-moving river of ice._____________________________ R A large, flowing body of water that usually empties into a sea or ocean. _____________________________ W The process in which water circulates from the oceans to the clouds to the land to the rivers, and then accumulates back into the oceans. _________________ 1.Which are the four layers of the atmosphere? 2.What happens to the oxygen in the air as you go up? 3.Where do natural water gets transformed into drinking water? 4.What gases can you find in the air? 5.How can we look after our air and our water? 6.What are the three estates of the matery? Can you give examples of each one?