CBSE Class 6 Science Revision Notes Chapter 14

CBSE Class 6 Science Chapter 14 Revision Notes – Water

CBSE Class 6 Science Chapter 14 discusses the most basic daily need of life, that is, Water. Water is necessary for the majority of household tasks, including bathing, washing, cooking, etc.

Some important concepts that are covered in Class 6  Science Chapter 14 are  given below.

  • How much water do we use?
  • Where do we get water from?
  • Water cycle
  • Loss of water by plants
  • How are clouds formed?
  • Back to the oceans
  • What if it rains heavily?
  • What happens if it does not rain for a long period of time?
  • How can we conserve water?

CBSE Class 6 Science Chapter 14 Revision Notes are provided by Extramarks.Subject matter experts review these and they are based on NCERT books.. Extramarks Revision Notes make it easy for students to revise right before exams effectively and efficiently. 

Revision Notes for CBSE Class 6 Science Chapter 14

Access Class 6 Science Chapter 14 – Water – Notes 

How much water can we use?

  • One-third of the earth’s surface is covered by water, including seas, oceans, glaciers, etc.
  • Only 2% of freshwater is usable for drinking and other purposes.
  • Water is used daily for cooking and other domestic purposes.
  • Both the industrial and agricultural sectors use water for sustaining livestock, irrigation, power generation, etc.

Where do we get water from?

  • Rivers, lakes, ponds, and wells, constitute 2% of the water that is suitable for human consumption and other uses.
  • Sea and ocean water are too salty for human consumption.
  • The water cycle helps transport water from the seas and oceans into rivers, lakes, ponds, and wells.
  • We also get water from glaciers as they melt.

Water Cycle

  • The water cycle, also known as the hydrologic cycle or the hydrological cycle, is the continuous movement of water on, above, and beneath the Earth’s surface.
  • The cycle involves the evaporation of water from the water bodies on the earth’s surface.
  • Through the process of transpiration, the plant’s water is also lost as vapour.
  • Condensation occurs as the water vapour is created and moved upward, resulting in minute droplets.
  • These minute droplets combine to form clouds. Water returns to the earth through the process of precipitation.
  • Infiltration is the process by which rainwater is absorbed into the ground.
  • Thus, water from the oceans and the earth’s surface enters the atmosphere as vapour, returns to the atmosphere as rain, hail, or snow, and eventually returns to the oceans. The water cycle refers to the circulation of water in this manner.

Back to the Oceans

  • Seas and oceans’ water surfaces are slightly lower than the land’s surface.
  • As a result, water from rain and glaciers flows into the oceans and seas.
  • Groundwater is refilled by the melting of snow and rainwater.
  • For human use, groundwater is the freshwater that exists below the surface of the earth.

What if it rains heavily?

  • Floods are brought on by increased water levels in bodies of water due to excessive rainfall.
  • Flood refers to an overflow of water that submerges land and causes damage.
  • Floods cause extensive damage to crops, domestic animals, property, and human life.
  • Additionally, it causes harm to infrastructure and disrupts the flow of clean water, leading to a water shortage.

What happens if it does not rain for a long period of time?

  • Water levels in bodies of water and groundwater drop without rain, and excessive transpiration causes a drought.
  • A drought is defined as a state in which there is no water available, not even for drinking.
  • A lack of water supplies caused by a drought eventually results in lost livelihoods because when a region experiences a drought, there is an extreme scarcity of food in that area. Food scarcity is referred to as famine. Because of the large population, many people die of hunger.

How can we conserve water?

  • Only a small portion of the water that is currently in surplus is available to us.
  • The demand for water consumption is rising along with the population.
  • Water shortages are caused by the careless use of this natural resource and by the rising demand.
  • Therefore, it is important to implement some measures through which water can be saved and conserved.
  • Sustainable water use can contribute to water conservation in the future.

Rainwater Harvesting

Rainwater collection is an important way to conserve freshwater supply. 

A method of preserving rain is through rainwater harvesting.

There are two different kinds of rainwater collection methods:

  • Rainwater is collected on the roof of the home and then channelled through a network of pipes to fill a pit or tank that is located below ground.
  • Direct rainfall entering the ground also helps rainwater collection naturally.

Rainwater collection has many advantages, including-

  • It reduces the need for water. 
  • It minimises the need for imported water.
  • Encourages water and energy conservation. 
  • Enhances the quantity and quality of groundwater.

FAQs (Frequently Asked Questions)

The term “water cycle,” also called “hydrologic cycle” or “hydrological cycle,” refers to the ongoing circulation of water on, above, and below the Earth’s surface. Water changes state through a number of processes, including evaporation, melting, and freezing, as well as sublimation, condensation, and deposition. All of these changes necessitate the use of energy. Evaporation occurs when water molecules on the surface of bodies of water become excited and rise into the air. These molecules with the greatest kinetic energy accumulate to form water vapour clouds.  At a certain height, the water vapour condenses into water dropletsThese eventually come together to form clouds. When enough droplets combine, it falls from the clouds to the ground below. This is known as precipitation (or rainfall). This process is called the water cycle

Plants can assist in the transfer of water vapour into the atmosphere. Water is essential for plant growth. These plants absorb moisture from the ground. Plants use some water to prepare food. Additionally, the plant’s fruits, roots, flowers, stems, and leaves all store this water. As a result, a portion of the water is released into the atmosphere by the leaves through transpiration. This process releases a significant amount of water vapour into the atmosphere.

Rainwater harvesting is the process of gathering and storing rainwater that runs off of rooftops, roads, parks, etc. The groundwater receives this water and stores it or recharges it.

The benefits of rainwater collection are as follows.

  • It is helpful in places with lower rainfall.
  • It contributes to rising groundwater levels.
  • It helps lessen the impact of the drought.
  • This method is essential in areas where there are no rivers or lakes and groundwater is the main source of drinking water.
  • It reduces soil and water pollution.