This is a PowerPoint presentation by ANJALI KUMARI of DELHI PUBLIC SCHOOL (bokaro,jharkhand India).CBSC

1. Water
A Precious
Reservoir

2. Introduction to water
 Water (H2O) is the most valuable asset and an inexhaustible
compound on the Earth's surface, covering in excess of 70% of the
planet.
 Water exists in three states in nature, namely, liquid, solid, and
gas.
 Water is the only common substance that is naturally found as
a solid, liquid or gas. Solids, liquids and gases are known as states
of matter. ... This animation explores water as
a solid, liquid and gas. The water molecules stay the same, but
they behave differently as they change from one form to another.

3. What is water?
 Water is an inorganic, transparent, tasteless, odorless, and nearly
colorless chemical substance, which is the main constituent of
Earth's hydrosphere and the fluids of all known living organisms.
It is vital for all known forms of life, even though it provides no
calories or organic nutrients.
 Water, a substance composed of the chemical elements hydrogen
and oxygen and existing in gaseous, liquid, and solid states.
 It is one of the most plentiful and essential of compounds .
 It has the important ability to dissolve many other substances.

4. Uses of water:-
 Water can be used for direct and indirect purposes.
Direct purposes include bathing, drinking, and cooking,
while examples of indirect purposes are the use of water in
processing wood to make paper and in producing steel for
automobiles.
 The bulk of the world's water use is for agriculture, industry,
and electricity.

5. Sources of water:-

6. Importance of Water:-
 Water allows the body to absorb and assimilate
minerals, vitamins, amino acids, glucose and other
substances.
 Water flushes out toxins and waste. Water helps to
regulate body temperature.
 Water acts as a lubricant for joints and muscles.
 Water boots energy. Water delivers important
nutrients to all of our cells, especially muscle cells,
postponing muscle fatigue.
 Water helps weight loss. Water helps you feel full
longer, without adding any additional calories.

7. Water in the human body:-

8. Water cycle:-
 The water cycle shows the continuous movement
of water within the Earth and atmosphere. It is a
complex system that includes many different
processes. Liquid water evaporates into water vapor,
condenses to form clouds, and precipitates back to
earth in the form of rain and snow.
 The water cycle, also known as the hydrologic cycle or
the hydrological cycle, describes the continuous
movement of water on, above and below the surface of
the Earth.

9. Water cycle {image}

10. Evaporation ,Condensation,Transpiration,
Precipitation,Runoff and Groundwater
 Evaporation is the process by which water changes from a liquid to a gas or
vapor. Evaporation is the primary pathway that water moves from the liquid
state back into the water cycle as atmospheric water vapor.
 Condensation is the change of the physical state of matter from the gas phase
into the liquid phase, and is the reverse of vaporization. The word most often
refers to the water cycle.
 Transpiration is the loss of water from a plant in the form of water vapor.
Water is absorbed by roots from the soil and transported as a liquid to the
leaves via xylem. In the leaves, small pores allow water to escape as a vapor.
 Precipitation is any product of the condensation of atmospheric water vapor
that falls under gravity from clouds. The main forms of precipitation include
drizzle, rain, sleet, snow, ice pellets, graupel and hail.
 That part of the precipitation, snow melt, or irrigation water that appears in
uncontrolled (not regulated by a dam upstream) surface streams, rivers, drains
or sewers is called runoff.
 Groundwater is the water present beneath Earth's surface in soil pore spaces
and in the fractures of rock formations. A unit of rock or an unconsolidated
deposit is called an aquifer when it can yield a usable quantity of water.

11. Rainwater Harvesting
 Rainwater harvesting is the collection and storage of
rain, rather than allowing it to run off. Rainwater is
collected from a roof-like surface and redirected to a
tank, cistern, deep pit, aquifer or a reservoir with
percolation. Dew and fog can also be collected with
nets or other tools.

12. Water Pollution
 Water pollution is the contamination of water bodies,
usually as a result of human activities. Water bodies
include for example lakes, rivers, oceans, aquifers and
groundwater.
 How to reduce water pollution :-
1. Do not pour fat from cooking or any other type of fat,
oil, or grease down the sink.
2. Do not dispose of household chemicals or cleaning
agents down the sink or toilet.
3. Do not flush pills, liquid or powder medications or
drugs down the toilet.
4. Avoid using the toilet as a wastebasket.
5. Avoid using a garbage disposal.

13. Causes and Effects of water pollution
On human health. To put it bluntly:- Water pollution kills. Waterborne
pathogens, in the form of disease-causing bacteria and viruses from
human and animal waste, are a major cause of illness from contaminated
drinking water. Diseases spread by unsafe water include cholera, giardia,
and typhoid.
 Causes:-
Discharge of domestic and industrial effluent wastes, leakage
from water tanks, marine dumping, radioactive waste and atmospheric
deposition are major causes of water pollution. Heavy metals that
disposed off and industrial waste can accumulate in lakes and river,
proving harmful to humans and animals.
 Effects:-
Some of these water-borne diseases are Typhoid, Cholera, Paratyphoid
Fever, Dysentery, Jaundice, Amoebiasis and Malaria. Chemicals in
the water also have negative effects on our health. Pesticides – can
damage the nervous system and cause cancer because of the carbonates
and organophosphates that they contain.

14. Water pollution {image}

15. Natural disasters by water:-
 Flood:-
 A flood is an overflow of water on normally dry ground.
This is most commonly due to an overflowing river, a
dam break, snowmelt, or heavy rainfall. Less commonly
happening are tsunamis, storm surge. The most
deadly flooding was in 1931 in China and killed between
2,000,000 and 4,000,000 people.
Drought:-
 A drought is a period of time when an area or region
experiences below-normal precipitation. The lack of
adequate precipitation, either rain or snow, can cause
reduced soil moisture or groundwater, diminished
stream flow, crop damage, and a general water shortage.

16. Flood and Drought {image}

17. Conclusion:-
 Hence, now the topic of water is very-very clear .
 It was a great topic we have discussed and now we are
able to solve all questions on this topic .
 This was a ppt by Anjali Kumari.