Introduction
Water is a transparent, tasteless and odourless liquid that is essential for all living beings. Water has several distinct properties that are important for the sustenance of life. It is important as a solvent that helps dissolve all the solutes of the body and facilitates several metabolic processes within the human body. There are several uses of water in daily life. It helps to flush out the toxins from our bodies. It plays a critical role in photosynthesis and is released during respiration.
Around 70% of the earth's surface is covered with water. However, only a small percentage (around 1%) of it is suitable for human consumption. There has been an exponential rise in the global population while the supply of water has remained fairly constant. Some of the sources of water like rivers and lakes are getting contaminated due to industrial pollution and poor policymaking.
Oceans and the frozen areas of the polar region hold a large portion of the global water content. The water cycle is a phenomenon where the water vapour created from oceans, lakes, and rivers condenses and returns to the earth through precipitation. The cycle includes evaporation, precipitation, and runoff as the transfer processes. Ponds, lakes, rivers, streams, and seas are some of the sources of water which depend on rains and the water cycle.
Human beings need water for hydration as we regularly lose water during breathing, sweating and digestion. The amount of water that is needed depends on the climate, kind of physical activity and health status of the individual. Other living beings are equally dependent on water for their survival. For plants, the moisture content of the soil helps them to grow.
Characteristics of Water:
Some of the characteristics of water are:
It is a polar inorganic compound.
The water molecule contains 2 hydrogen atoms and 1 oxygen atom.
Its chemical formula is H2O.
The freezing point of water is 0˚C.
The boiling point of water is 100˚C.
The Hydrologic Cycle of Water
The continuous circulation of water in the Earth atmosphere is known as the Hydrologic cycle of water. There are many processes involved in the Hydrologic cycle; the important processes that the students will learn today are evaporation, transpiration, condensation, precipitation and runoff. Now let us look at all these processes in detail.
Evaporation: This process involves a change of state of a substance from water to gas. The evaporation process needs the energy to take place. The source of energy could be Earth, the atmosphere, the sun, humans or any objects on the surface of Earth. For example, a human body sweats after exercise or even due to a temperature change, secreting water on the skin. The basic purpose of this process is to cause the body to use its heat to evaporate the liquid by removing the heat and cooling down the body.
Transpiration: This process involves the evaporation of water from plants through stomata. Stomata are connected to the vascular plant tissue and are small openings that are found on the underside of the leaves. The transpiration process is caused by the humidity in the atmosphere and the moisture present in the soil. Only 1% of the transpired water is used by the plants and the rest 90% is passed into the atmosphere.
Condensation: This process involves a change of water vapour present in the earth atmosphere to change to a liquid state. Clouds or dews are examples of atmosphere condensation. For example, the droplets of water that we see on cold drink bottles. The change of temperature results in the water vapour changing into liquid. Condensation does not take place because of the change of the temperature but the difference in temperature is considered that is the air and dew point temperature (Dew can be formed). Cooling causes the vapour to condense. We must have observed fog, the foggy condition is the result of the air and dew point temperature being the same. Condensation and Evaporation are two opposite processes.
Precipitation: This process involves the particles formed by the condensation process to grow large. This could result through coalescence or collision, by the rising air and thus falls to the earth. Precipitation can be in the form of rain, snow, etc. This process is the source of freshwater that we receive on Earth.
Runoff: This process involves the process when the water cannot be absorbed anymore due to an excess amount of precipitation. Lakes, ponds and rivers are a few examples of runoff. Evaporation of this runoff sets the cycle all over again.
What are the Uses of Water?
There are many different uses of water, and this life-giving resource comes in handy to accomplish everything from our daily chores to helping entire industries function.
Domestic Uses of Water
Water is important for cooking and helps in boiling, steaming and simmering food. Water has unique properties to form solutions and emulsions which make it an effective agent to help in washing clothes, dishes, and food items. Washing with water helps in removing impurities. It is required for taking showers, brushing teeth and maintaining personal hygiene. It is used for gardening at home. Water is used in several home appliances like air coolers. Water is used to generate electricity which is consumed for domestic purposes.
We lose the water in our bodies during breathing, sweating, and digestion. The water content of the body should be replenished by drinking regularly to avoid dehydration and other health problems. Around 1 to 7 litres of water is recommended per day to avoid dehydration
Uses of Water in Agriculture
A large percentage of water is used in agriculture annually. Agriculture requires large quantities of water to grow fresh produce and sustain livestock. It is used for irrigation, pesticide and fertiliser application, frost control and crop cooling. Proper usage of water is important to manage crop yield and productivity. Farmers should follow several water conservation strategies for sustainable agriculture.
Plants use water and sunlight for photosynthesis and produce oxygen. Agricultural water comes from surface water (rivers, streams, open canals, ponds, reservoirs and lakes), groundwater from wells and rainwater. Water is used in all traditional agriculture methods including the cultivation of rice, wheat, sugarcane, etc.
Water quality can be affected by rampant industrialization and the illegal disposal of chemicals in water and the atmosphere. Poor water quality affects the quality of the food crop and may also cause several diseases. Water contamination is the main reason for food contamination and illnesses related to the contamination. Groundwater is a safe source of quality water.
Water is used for livestock, dairies, and fish farms.
Industrial Uses of Water
Water is used in hotels, motels, restaurants, offices, and other commercial facilities.
It is essential in the manufacturing and production of paper, chemicals, automobiles, steel, food, textile production, dying, etc. Power plants need a significant amount of water for cooling.
Water is a universal solvent and hence is used to dissolve several compounds in industrial production. It is widely used as a solvent and less commonly used as a catalyst. Water vapour is also used in several industrial processes. Water is used by smelting facilities and petroleum refineries.
Industrial uses of water are processing, diluting or fabricating a product. Rivers, canals, oceans, and seas provide simple means of transportation. There will be less friction in the water compared to land transport without any obstacles. It offers economic opportunities with an effective way to transport cargo.
Water is a source of hydroelectricity. Dams are constructed across rivers and lakes to store water which is converted to electricity using turbines. Hydroelectricity is a renewable energy source that is used across the globe. It has reduced the dependence on fossil fuels for energy.
Water is used in the extraction of minerals, oil, and gases. It is essential for several critical mining functions. Along with being a solvent, water is used in a steam turbine and heat exchanger.
Medicinal Uses of Water
Water has several medical uses especially in hemodialysis and dental procedures. It is used to wash surgical tools and equipment. It is also essential for hydrotherapy.
Contamination of water with pathogens is an important concern in the healthcare setting as the immune system is weakened in some patients. The waterborne disease can spread through direct contact, ingestion, in-direct contact, and inhalation, aspiration of water and blood contact. Water should be thoroughly treated before it is used in hospitals and clinics. Clinicians should take appropriate measures to avoid contaminating water that will be ingested by the patient.
Top 5 Causes of Outbreaks Related to Water Contamination are:
Legionella
Giardia
Campylobacter
E. coli
Cryptosporidium, Hepatitis A, Mycobacterium, Norovirus, Pseudomonas, Salmonella
Thus, pure water should be available for drinking to avoid such epidemics.
FAQs on Uses of Water
1. What are the four main categories for the uses of water?
Water usage is broadly classified into four main categories based on its application. These are:
- Domestic Use: Water used in households for daily activities like drinking, cooking, cleaning, and sanitation.
- Agricultural Use: Water required for farming activities, primarily for irrigation, as well as for livestock and crop cooling.
- Industrial Use: Water essential for manufacturing processes, cooling systems in power plants, as a solvent, and for transportation.
- Medical Use: Purified water used in healthcare for procedures like hemodialysis, hydrotherapy, and sterilising equipment.
2. What are some common examples of how water is used in our daily domestic life?
In our homes, water is essential for a wide range of activities. Common domestic uses include drinking to stay hydrated, cooking methods like boiling and steaming, maintaining personal hygiene through bathing and brushing, washing clothes and dishes, gardening, and operating home appliances like air coolers.
3. What is the importance of water in agriculture?
Water is fundamentally important for agriculture, which is the largest consumer of water globally. Its primary role is in irrigation to help crops grow. It is also used for applying pesticides and fertilisers, controlling frost, and cooling crops. The survival of livestock and the operation of fisheries and dairies are also entirely dependent on a consistent supply of water.
4. Why is water often called the "universal solvent," and how does this property benefit industries?
Water is called the universal solvent because its polar nature allows it to dissolve more substances than any other liquid. This property is incredibly valuable for industries. It is used to dissolve raw materials in the production of chemicals, paper, and textiles. It also acts as a powerful cleaning agent to wash away impurities and is used to dilute products to the correct concentration during the manufacturing process.
5. How is water used to generate hydroelectricity?
Water is used to generate hydroelectricity, a renewable energy source. This process involves building a dam across a river to create a large reservoir of stored water. When released, the force of this water flows through pipes and spins the blades of a turbine. The turbine is connected to a generator, which converts the mechanical energy of the spinning turbine into electrical energy.
6. Beyond just drinking, what are the most vital functions of water in the human body?
While hydration is crucial, water performs several other vital functions in the human body. It acts as a solvent to transport essential nutrients and minerals to cells, facilitates critical metabolic and enzymatic reactions, helps regulate body temperature through sweating, and is essential for flushing out toxins and waste products from the body.
7. What is the difference between surface water and groundwater as sources for drinking?
The main difference lies in their origin and susceptibility to contamination. Surface water is collected from sources open to the atmosphere, such as rivers, lakes, and reservoirs. It is easily accessible but also more prone to pollution. Groundwater is found underground in aquifers and rock spaces. It is typically safer as it gets naturally filtered by layers of soil and rock, but it can be harder to access and may contain dissolved minerals.
8. What are the key processes that make up the water cycle (hydrologic cycle)?
The water cycle, or hydrologic cycle, is the continuous movement of water on, above, and below the surface of the Earth. The key processes involved are:
- Evaporation: The process where liquid water turns into water vapour (a gas).
- Transpiration: The evaporation of water from plants through their leaves.
- Condensation: The process where water vapour in the air cools and changes back into liquid water, forming clouds.
- Precipitation: Water released from clouds in the form of rain, snow, sleet, or hail.
- Runoff: The flow of water over the land surface when precipitation exceeds the soil's absorption capacity.
9. How can poor water quality from industrial or domestic sources affect our health and food supply?
Poor water quality poses a dual threat. For health, drinking water contaminated with pathogens or chemicals can lead to severe gastrointestinal illnesses, neurological disorders, and other diseases. For the food supply, when contaminated water is used for irrigation, these harmful substances can be absorbed by crops. This not only affects crop yield but can also transfer contaminants to humans who consume the produce, leading to foodborne illnesses.
10. What are the basic physical properties that help us identify pure water?
The primary physical properties of pure water are determined by our senses. Pure water is characteristically transparent and colourless, meaning it has no colour. It is also tasteless and odourless. In terms of its physical constants, its freezing point is 0°C and its boiling point is 100°C at standard atmospheric pressure. Any deviation from these properties often indicates the presence of impurities.
