Water: Class 6 Science Q&A
53 free answers on Water (Science) for Class 6 students, across CBSE, ICSE and State boards. Includes questions such as “Water Conservation”, “Everyday Observations Related to Water”, “Importance of Dissolved Oxygen”.
Question & Answer
Questions
- ScienceClass 6CBSE
Water Conservation
Water is a limited resource, so it must be used wisely. We can conserve water by: Avoiding wastage Repairing leaking taps Using water carefully in daily activities Not polluting rivers and ponds Practicing rainwater harvesting Planting trees and protecting forests
- ScienceClass 6CBSE
Uses of Water
Water is used in many ways in our daily life: Drinking, cooking, bathing, and cleaning Agriculture for growing crops Industries for manufacturing processes Generating electricity (hydropower)
- ScienceClass 6CBSE
Everyday Observations Related to Water
We often observe condensation in daily life. For example, when we breathe on spectacles, they become wet because water vapour in our breath condenses on the cooler glass surface. Similarly, when a cold water bottle is taken out of a refrigerator, water droplets form around it. This happens because water vapour in the surrounding air condenses on the cold surface of the bottle.
- ScienceClass 6CBSE
Importance of Dissolved Oxygen
Fish and aquatic plants survive in water because it contains dissolved oxygen. Although oxygen is only slightly soluble in water, it is sufficient for aquatic organisms to breathe and live.
- ScienceClass 6CBSE
Natural Phenomena Related to Water
Fog is formed when water vapour condenses on dust particles near the surface of the Earth, especially during winter. It appears as a thick cloud close to the ground. Floods are caused by excessive rainfall, leading to overflow of rivers and water bodies. On the other hand, droughts occur when there is no rainfall for a long period (usually a year or more), resulting in severe water shortage. During dro
- ScienceClass 6CBSE
Special Water Processes
Transpiration is the process by which plants release excess water into the air through tiny pores in their leaves. This water vapour contributes to the water cycle. Rainwater harvesting is the method of collecting and storing rainwater for future use. It helps conserve water and is especially useful in areas facing water scarcity. Water is called a universal solvent because it can dissolve many substan
- ScienceClass 6CBSE
Forms and Sources of Water
Water exists in three states: Solid (Ice) Liquid (Water) Gas (Water vapour) Natural sources of water include rivers, lakes, oceans, ponds, wells, and streams. Water found on the surface of the Earth, such as rivers and lakes, is called surface water, while water stored underground in wells and aquifers is known as groundwater. However, sea
- ScienceClass 6CBSE
Evaporation, Condensation, and Water Cycle
Evaporation is the process by which water changes into water vapour due to heat, especially on sunny days. When the sun heats water bodies like rivers, lakes, and oceans, water slowly turns into vapour and rises into the atmosphere. Condensation is the opposite process of evaporation. It occurs when water vapour cools down and changes back into liquid water. This happens when vapour comes in contact with cooler surfaces or air
- ScienceClass 6CBSE
Water and Its Processes – Explanation
Water is one of the most essential natural resources on Earth. It is necessary for the survival of all living beings, including humans, animals, and plants. Water exists in different forms and continuously moves in nature through various processes such as evaporation, condensation, and precipitation.
- ScienceClass 6CBSE
Write a short note on the water cycle.
The water cycle is the continuous movement of water on, above, and below the surface of the Earth. It involves several processes such as evaporation, condensation, precipitation, and collection. Water from oceans, rivers, lakes, and plants evaporates due to the heat of the sun and rises into the atmosphere as water vapour. This vapour cools and condenses to form clouds. When the clouds become heavy, water falls back to the Earth as rain, snow, or hail, which i
- ScienceClass 6CBSE
Why does the rate of evaporation increase on increasing the temperature?
Evaporation is the process by which a liquid changes into vapour. When the temperature increases, the particles of the liquid gain more kinetic energy. Because of this increased energy, the molecules move faster and are able to overcome the forces holding them together in the liquid state. As a result, more molecules escape from the surface of the liquid into the air as vapour. Therefore, higher temperature increases the rate of evapor
- ScienceClass 6CBSE
How are rivers and streams formed?
Rivers and streams are formed mainly from rainwater and melting snow. When snow on mountains melts, it turns into water and flows downhill due to gravity. This flowing water forms small channels called streams. Many streams join together to form rivers, which flow across land for long distances. Rivers collect water from rainfall, tributaries, and groundwater along their path. Eventually, most rivers empty into lakes, seas, or oceans.
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Why is water used as a coolant in engines?
Water is used as a coolant in engines because it has a high specific heat capacity, which means it can absorb a large amount of heat without a significant rise in temperature. During the combustion of fuel in an engine, a large amount of heat is produced. Water circulating in the radiator system absorbs this heat and carries it away, preventing the engine from overheating. By cooling the engine, water helps in:
- ScienceClass 6CBSE
Which process is involved in the removal of salt from sea water?
Ans. The process used to remove salt from seawater is called desalination. This process converts saline water into fresh water suitable for drinking and other uses. One common method of desalination involves evaporation followed by condensation. In this method, seawater is heated so that water evaporates and leaves the salt behind. The water vapour is then cooled and condensed to form pure water. Another modern method is reverse
- ScienceClass 6CBSE
What is the role of transpiration in plants?
Transpiration is the process by which plants lose water in the form of water vapour from the surface of their leaves through small openings called stomata. Transpiration plays several important roles in plants: It helps in cooling the plant during hot weather. It helps in the transport of water and minerals from roots to other parts of the plant. It maintains the water bala
- ScienceClass 6CBSE
Is there any variation in the amount of water present on the earth?
Ans. No, the total amount of water present on Earth remains almost constant. Water continuously circulates between the oceans, atmosphere, land, and living organisms through the water cycle. In this cycle, water evaporates from oceans, lakes, and rivers into the atmosphere, forms clouds through condensation, and returns to the Earth as precipitation in the form of rain, snow, or hail. This continuous circulation maintains the balance of water on Earth.</
- ScienceClass 6CBSE
How does rainwater harvesting increase the water level of underground water?
Rainwater harvesting is the process of collecting and storing rainwater for future use. In this method, rainwater from rooftops or open areas is directed into storage tanks or allowed to seep into the ground through pits and recharge wells. When rainwater seeps into the soil, it recharges underground water sources and raises the water table. This helps in: Increasing groundwater levels Reducing water
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Why does ice float on the surface of water?
Ice floats on water because it is less dense than liquid water. When water freezes, its molecules arrange themselves in a fixed crystal structure with spaces between them. This structure occupies more volume and reduces the density of ice. Since substances with lower density float on substances with higher density, ice floats on the surface of water. This property is very important for aquatic life because lakes and ponds freeze only at the surface while water
- ScienceClass 6CBSE
Why is water called a universal solvent?
Water is called the universal solvent because it can dissolve a large number of substances compared to most other liquids. Many solids, liquids, and gases dissolve easily in water. For example, salt, sugar, minerals, and gases like oxygen and carbon dioxide dissolve in water. This property of water is very important in nature and in living organisms. It helps in: Transporting nutrients in plants and animals <
- ScienceClass 6CBSE
How much percentage of salt is present in salt water?
Seawater contains a large amount of dissolved salts, which makes it salty. On average, seawater contains about 3.5% dissolved salts. These salts include sodium chloride (common salt) along with salts of calcium, magnesium, potassium, and sulphates. Because of this high salt content, seawater is not suitable for drinking unless the salt is removed through desalination processes.