Water
CHEMISTRY SSS1 Third Term
WEEK 1
Water
Performance Objectives
The student should be able to:
- List the sources of water
- List and explain the two types of water.
- Explain what water pollutant is
- Give at-least four uses of water
Content
Water
Water is a chemical substance composed of hydrogen and oxygen existing in gaseous, liquid, and solid tastes that is essential to all known forms of life. Water is a clear, colorless, odorless, tasteless liquid that freezes into ice below 0 degrees centigrade and boils above 100 degrees centigrade.
The chemical formula of water is hydrogen oxide (H2O) and it has the important ability to dissolve many other substances. Indeed, the versatility of water as a solvent is essential to living organisms.
Life is believed to have originated in the aqueous solutions of the world’s oceans, and living organisms depend solely on aqueous solutions, such as blood and digestive juices, for biological processes.
In small quantities, water appears colorless, but water actually has an inherent blue color caused by slight absorption of light at red wavelengths.
Although the molecules of water are simple in structure (H2O), the physical and chemical properties of the compound are extraordinarily complicated, and they are not typical of most substances found on Earth.
Water is vital both as a solvent in which many of the body’s solutes dissolve and as an essential part of many metabolic processes within the body. Metabolism is the sum total of anabolism and catabolism.
In anabolism, water is removed from molecules (through energy requiring enzymatic chemical reactions) in order to grow larger molecules (e. g. starches, triglycerides, and proteins for storage of fuels and information).
Sources of water
Water is one of the vital elements needed in our day to day activities as a living being. Water is not just essential to our health, but we also use it for numerous household tasks such as cooking, bathing, cleaning, and drinking; but how often do we think about its source? Where does our water come from? How is it treated? How do we know it is safe to drink? and many other questions we ought to raise.
However, there are two major sources of water which are surface water and groundwater. Surface Water is found in lakes, rivers, and reservoirs. Ground water lies under the surface of the land, where it travels through and fills openings in the rocks.
Ground Water
Groundwater is water that is found underground within rocks. Its presence depends primarily on the type of rock. Permeable rocks have tiny spaces between the solid rock particles that allow water and other fluids to pass through and to be held within the rock structure. The layers of rock that hold groundwater are called aquifers.
Groundwater in an aquifer is replenished by rain and other forms of precipitation (any form of water, such as rain, snow, sleet or hail that falls to the Earth’s surface. The level of water below the ground is called the water table. Groundwater can be extracted from wells or collected from springs.
Surface Water
Surface water is easily the most abundant supply of natural water. The downside is that most of the surface water on the planet is saltwater so it is not ideal for drinking for most living species. Surface water does play an important part in our daily lives in addition to being a source of drinking water.
Surface water is used to produce hydro-electric power as a clean energy source that is also renewable. Surface water is supplied by precipitation, springs, and ice melting from higher elevations and glaciers.
Examples of surface water include lakes, ponds, streams, rivers, oceans storage reservoirs, etc.
Types of water
Hard water
What is hard water?
Hard water is the excessive presence of calcium and magnesium – two naturally-occurring minerals in the water. The higher amount of these minerals that are present in water, the higher it will rank on the hard water scale. While both essential to everyday health, calcium and magnesium are not essential for water usage. In fact, hardness in water can have detrimental effects on your home.
When using water for cleaning purposes, you may notice spots or a film of residue on your dishes, shower, or clothing. Not to mention, you may find particles inside of your appliances like the dishwasher or laundry machine. When hard water is heated, calcium deposits can form. If this builds up, it can greatly damage the performance and lifespan of your appliances. This includes your pipes and even your coffee machine. To make matters worse, your heating costs will skyrocket and the efficiency of your appliances will plummet. If your water is high on the water hardness scale, you might also notice effects on your personal hygiene. Hard water can leave a feeling of residue on your hands, skin, and hair upon washing. As a result, your hair and skin may feel more dry and brittle.
It is up to your water supplier to test water hardness before distributing it to your community. Luckily, you can still combat water hardness by softening your water. Using a water softener can reduce impurities in your water, including calcium and magnesium. What does this mean for you and your home? Cleaner water, appliances, hair, and skin.
Soft water
What is soft water?
Unlike hard water, soft water is free of harsh minerals that can damage your home and your body. In other words, it is more gentle on your body and your home. Without calcium and magnesium, soft water can prevent scale buildup around your home including your appliances and pipes. Best of all, it increases the effectiveness in soap compared to hard water which can inactivate the soap’s ingredients. In regard to health, soft water can combat the dryness and stickiness caused by cold weather, low humidity, and hard water. What does this mean for your body? Softer, silkier hair and skin after every wash. Systems like Culligan’s Water Softeners can help soften water so you achieve more efficient cleaning in your home.
Water pollutants
Agricultural
Not only is the agricultural sector the biggest consumer of global freshwater resources, with farming and livestock production using about 70 percent of the earth’s surface water supplies, but it’s also a serious water polluter. Around the world, agriculture is the leading cause of water degradation. In the United States, agricultural pollution is the top source of contamination in rivers and streams, the second-biggest source in wetlands, and the third main source in lakes. It’s also a major contributor of contamination to estuaries and groundwater. Every time it rains, fertilizers, pesticides, and animal waste from farms and livestock operations wash nutrients and pathogens—such bacteria and viruses—into our waterways. Nutrient pollution, caused by excess nitrogen and phosphorus in water or air, is the number-one threat to water quality worldwide and can cause algal blooms, a toxic soup of blue-green algae that can be harmful to people and wildlife.
Sewage and wastewater
Used water is wastewater. It comes from our sinks, showers, and toilets (think sewage) and from commercial, industrial, and agricultural activities (think metals, solvents, and toxic sludge). The term also includes stormwater runoff, which occurs when rainfall carries road salts, oil, grease, chemicals, and debris from impermeable surfaces into our waterways
More than 80 percent of the world’s wastewater flows back into the environment without being treated or reused, according to the United Nations; in some least-developed countries, the figure tops 95 percent. In the United States, wastewater treatment facilities process about 34 billion gallons of wastewater per day. These facilities reduce the amount of pollutants such as pathogens, phosphorus, and nitrogen in sewage, as well as heavy metals and toxic chemicals in industrial waste, before discharging the treated waters back into waterways. That’s when all goes well. But according to EPA estimates, our nation’s aging and easily overwhelmed sewage treatment systems also release more than 850 billion gallons of untreated wastewater each year.
Oil pollution
Big spills may dominate headlines, but consumers account for the vast majority of oil pollution in our seas, including oil and gasoline that drips from millions of cars and trucks every day. Moreover, nearly half of the estimated 1 million tons of oil that makes its way into marine environments each year comes not from tanker spills but from land-based sources such as factories, farms, and cities. At sea, tanker spills account for about 10 percent of the oil in waters around the world, while regular operations of the shipping industry—through both legal and illegal discharges—contribute about one-third. Oil is also naturally released from under the ocean floor through fractures known as seeps.
Radioactive substances
Radioactive waste is any pollution that emits radiation beyond what is naturally released by the environment. It’s generated by uranium mining, nuclear power plants, and the production and testing of military weapons, as well as by universities and hospitals that use radioactive materials for research and medicine. Radioactive waste can persist in the environment for thousands of years, making disposal a major challenge. Consider the decommissioned Hanford nuclear weapons production site in Washington, where the cleanup of 56 million gallons of radioactive waste is expected to cost more than $100 billion and last through 2060. Accidentally released or improperly disposed of contaminants threaten groundwater, surface water, and marine resources.
Uses of water
water molecule is made up of 3 atoms. 2 atoms of hydrogen and one atom of oxygen. They have an imbalanced structure and this makes them stick and attract different substances. It is a chemical substance that is tasteless, odorless, colorless, and transparent. It is chemically represented as H₂O. It is mostly used in making fertilizers. Its boiling point is 100 degrees Celsius and the melting point is 0-degree celsius. In the process of sweating, digestion, breathing body loses water content. Therefore it is very important to drink water to keep it hydrated. Let’s see some other uses of water
List of uses of water
Water is stored in various parts of the world but not evenly distributed all over the earth. It is said to be a universal solvent. Various sources of water are – sea, lake, rain, well, stream, borehole, and pond. It is used for washing, drinking, generating electricity, etc. Below are the different uses of water in various fields:
- Domestic uses of water
- Water use for agriculture
- Industrial uses of water
Domestic uses of water:
15 % of water is consumed for domestic purposes. Water is used for drinking, bathing, cooking food and washing dishes, clothes, fruits, vegetables, and brushing teeth.
Water use for agriculture:
Agriculture is the largest consumer of water. About 70% of water is used for irrigation. Water is necessary for gardening, farming, and fisheries. Plants require water to grow. During the process of photosynthesis, they consume water. To yield crops, fruits, flowers, vegetables they need sufficient water, manure, sunlight, and oxygen.
Industrial uses of water:
It is either used in creating or to cool the equipment used for creating the product. Industrial water is used for washing, cooling, processing, transporting, diluting, or fabricating a product. The maximum amount of water is used in the production of chemicals, paper, and food.
Other uses are – it is used in transportation, manufacturing, hydroelectric power, removal of body wastes, tourism, and recreation.