What are the four Elements?

Science Lesson: Earth, Water, Air, and also Fire

The old Greeks thought that there were four facets that whatever was consisted of of: earth, water, air, and fire. This theory was suggested approximately 450 BC, and also it was later on supported and added to through Aristotle.

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(Aristotle additionally suggested that there was a 5th element, aether, since it seemed strange that the stars would be made the end of earthly elements. He would certainly be surprised to discover that they space in fact consisted of of many aspects found top top earth, and are so hot they could be stated to it is in on fire all the time!)

The idea that these four aspects – earth, water, air, and fire – made up all issue was the cornerstone the philosophy, science, and also medicine for 2 thousand years (kids love to ask concerns on the elements).

The elements were “pure” yet could no be found in that state top top earth. Every visible point was comprised of some mix of earth, water, air, and fire.

The four aspects were also used to defined the 4 temperaments a person could have, and Hippocrates supplied the four aspects to explain the four “humors” discovered in the body. This theories stated that the temperaments and also humors necessary to be in balance through each various other in order for a person to be fine both mentally and physically.

While us do recognize now the these vault theories room false, in a means the four aspects do align through the four states of matter that modern science has actually agreed on: solid (earth), liquid (water), gas (air), and plasma (fire).

Although the Greeks believed that the four facets were unchanging in nature, every little thing was consisted of of various elements, i beg your pardon were hosted together or propelled apart by forces of attraction and also repulsion, leading to substances to appear to change. This is comparable to what yes, really happens with elements and all molecule at an atom level.

Matter is something that has actually mass and volume and is consisted of of atoms, which are the the smallest particles of matter. Bonding occurs among atoms to make larger molecules. (Click here to learn an ext about bonding.) Mass is exactly how much issue is in things whereas volume is just how much space the thing takes up. Just how atoms space arranged in things determines even if it is it is a solid, liquid, gas, or plasma.

In a solid, the atoms are packed closely together in an bespeak pattern and also cannot move, giving a hard a definite volume and also shape. Examples of solids incorporate rocks, wood, metal, and ice.In a liquid, the atoms space close together yet can move about each other. This permits a fluid to take it the form of whatever container it is put in. Examples of liquids incorporate room temperature water, room temperature mercury, and hot lava (molten rock).In a gas, there is more space in between atoms. The atoms have the right to move so freely that if the gas is no trapped in a container, the atoms will certainly diffuse and also spread transparent the atmosphere. Instances of gases space oxygen and also nitrogen (in the air we breathe), helium, and steam (water vapor).In a plasma, the atoms are spaced likewise to gas except there is for this reason much energy in a plasma, the atom actually break-up into smaller sized pieces. Plasmas room able to lug an electric current and also generate magnetic fields. Instances of plasmas incorporate lightning, solar wind, the sun, fluorescent lights, and neon signs.

Temperature plays crucial role in just how the atoms space aligned in a substance. As a general dominance of thumb, the colder the issue is, the closer the atoms are to each other, and also the warmer the matter is, the aside from that the atoms are apart. Of course, the temperature in ~ which a matter is a hard or a liquid depends on what substance the matter is do of. For example, water in ~ room temperature is a fluid whereas a rock at room temperature is solid.

Science Lesson: The Four elements in daily Life

First Element: Earth


The earth is complete of a wide selection of rocks and also minerals which gives the soil to grow vegetation and also support life. The two most common facets in the earth’s crust room oxygen (46%) and also silicon (28%). Due to the fact that of this, the most abundant mineral in the earth’s tardy is silica (silicon dioxide). An ext commonly known as sand, silica is a major component that glass. How can glass it is in made out of sand? Interestingly, when silica is heated, the melts and becomes glass, hardening as it cools.

Rich store of steel ores are found throughout the earth’s crust. While these steels are used in the production of machinery, tools, buildings, and also weapons, right out that the earth these metals are pretty useless. Fire is provided to heat, refine, and shape metal so that machines, hammers, and support beams can be make from it.

It is basic to think the the earth as being solid dust through and also through, but in truth it is comprised of number of layers. While countless of this layers space solid, the layer the surrounds the main point is dubbed the liquid outer core. It is so hot inside the planet that the rock at this layer has actually actually melted. The hard inner core is just as hot as the fluid layer surrounding it, yet the push on the inner main point is so great that scientists believe it is “pressed” into a solid.

Second Element: Water

Water has numerous unique properties. The chemical formula that water is H20, an interpretation it is do of 2 hydrogen atoms bonded to one oxygen atom. The hydrogen atoms each attach to one next of the oxygen atom and have a optimistic charge vice versa, the oxygen atom has a an unfavorable charge. This polarizes the water molecule, much like a magnet, giving a water molecule confident and an adverse ends.

Since opposite charges attract, water molecules tend to “stick” together. This gives water surface stress and anxiety and enables objects, such together paperclips, come float ~ above it.

While the can’t dissolve everything, water is recognized as the universal solvent because it deserve to dissolve much more substances than any other liquid. It can dissolve salt, sugar, acids, alkalis, some gases, and organic material.


Water traveling with your body or with the ground takes chemicals, minerals, and nutrients through it. Water’s capability to dissolve building materials helps keep the world healthy. For more than a century, the burn of fossil fuels has pumped huge amounts of carbon dioxide (CO2) right into the atmosphere. The water in seas have soaked up about fifty percent of this CO2 by dissolve the gas from the air and also processing that by sea vegetation.

Water has actually a high specific heat index, meaning that that takes a lot of of energy to readjust its temperature. This is essential for life to make it through on a planet. The diversity of water ~ above the earth keeps the planet in a very short however comfortable temperature range. The mean surface temperature of the planet is 59 ° F v the highest possible recorded temperature 135.9 ° F and also the lowest taped temperature -128.6 ° F.

To compare, it would seem logical the Mercury, the closest earth to the sun, would stay really warm on every surfaces that the planet, regardless if that was facing the sunlight or not. However, while the surface facing the sunlight does reach very warm temperatures (up come 800 ° F), the surfacing dealing with away from the sun drops to a chilly -280 ° F. Mercury’s absence of water is responsible for this correctly temperature change because the dry material that provides up its surface ar cannot hold warm like water does.

To experience for yourself exactly how well water does keep temperature native drastic fluctuations, pay fist to the readjust between daytime and nighttime temperatures the following time you visit a marine (near the ocean) or desert climate. You’ll probably an alert there is small to no temperature readjust near the ocean, conversely, in the desert over there is a significant change in daytime and also nighttime temperatures.

This high details heat index likewise helps water put out fire through cooling the fuel surfaces the the fire is burning, remove the warm needed for the fire to burn. Water additionally smothers a fire by staying clear of it from gaining the oxygen it requirements to burn.

Third Element: Air

Air was taken into consideration a “pure” element, however in fact the air that’s all about us is made up of a range of gases: mostly nitrogen and oxygen, with nearly 1% argon and even smaller amounts of carbon dioxide and also other aspects such together krypton and also helium. The composition of air is simply right because that life ~ above Earth, though.


We use a many the oxygen we gain from the air, then breathe the end carbon dioxide – which plants have to manufacture their food through photosynthesis. Tree in turn give off oxygen during photosynthesis.

Although waiting is invisible (and many of the time we forget the is even there), the does take it up space, it has actually volume, and also it exerts pressure. This have the right to be seen when you take it an “empty” glass, revolve it upside down, and shot to push it under to the bottom the a sink complete of water.

(You have the right to see how air expands when heated and shrinks as soon as cooled v this egg-in-a-bottle project.)

If the glass was truly empty, the water would quickly fill the within of the glass. Yet air is in there, and only a tiny amount the water can go into the glass. The waiting in the glass was compressed, offering the water some room that was previously inhabited with air.

It is a good thing that air fills empty room because wait all roughly us actually presses under on us all the time. We would collapse under the weight of the air, other than air is additionally inside us and exerts press that balances the end the pressure exerted by the outside air.

Fourth Element: Fire

How walk fire work? It’s carefully linked come air. Fire requirements three points in order come exist: oxygen, fuel, and also heat.

The intensity of a fire varies due to the fact that it is dependence on the oxygen, fuel, and heat available to it. When all 3 of this things space in a regulated situation, such together in candles or a campfire, fires are taken into consideration helpful. However when one or an ext of these things room not controlled, such as in a wildfire or a burning building, fires can conveniently become really dangerous.

To extinguish a fire, the oxygen, fuel, or heat needs to it is in removed. “Smothering” a fire by place a ceiling or dirt on the works since the fire goes out without oxygen. The earth provides wealth of fuel in the form of wood and also fossil fuels such as coal. As soon as the fuel is removed, the fire has actually nothing left come burn and is extinguished. Water frequently serves as an effective cooling source by remove the warmth from a fire. This is viewed when hot lava from an erupting volcano beginning the s or once a bucket of water is dumped ~ above a campfire.


Fire creates light, heat, and smoke by a rapid chemical reaction referred to as combustion. Smoke is the an outcome of the incomplete combustion (burning) of a fuel. Particles that were no burned become suspended in the air. Exhilaration is often dangerous since it has harmful gases that deserve to poison a human being who inhales too lot smoke.

You might be surprised to know that our bodies additionally use “combustion” to develop energy indigenous oxygen and food v metabolic processes. We need a secure supply that oxygen to save our bodies functioning normally; if there’s too small oxygen in the air, we’ll suffocate. In ~ the same time, we deserve to be thankful there’s not much more oxygen in the air, or the chemical reactions in our body would speed up, resulting in us to soon “crash and burn”!

Too lot oxygen in the air would also increase the danger of fires on the earth. Because nitrogen and argon space not very reactive, air is pretty for sure for us.

Science Projects: exploring The four Elements

Make a Fire Extinguisher

In order to put out a fire, one of three things have to be eliminated from it: heat, fuel, or oxygen. Learning this, firefighters don’t always use water to put out a fire.

What you Need:Empty soda bottle5 tablespoons that vinegar1/2 tablespoon of baking sodaTea light candleWhat girlfriend Do:

1. Light the candle.

2. To water the vinegar right into the bottle and add the baking soda. (You may want to use a funnel.) The mixture need to fizz.

3. Organize the party sideways end the lighted candle, making sure no liquid escapes. What happens to the flame?

What Happened:

The baking soda and vinegar react to make carbon dioxide, a gas that is heavier 보다 oxygen. As it “pours” the end of the bottle, that pushes the lighter oxygen away from the candle. The fire, now deprived the oxygen, have the right to no longer burn.

Traveling Nutrients

Water is often referred to as the global Solvent due to the fact that it deserve to dissolve an ext substances than any kind of other liquid, frequently carrying these liquified particles through it. When water travels v soil, nutrients (food) and also dissolved particles travel v the water to it is in deposited somewhere else. Here is one experiment to visually show how this process happens.

What friend Need:1/2 cup dry soil1/2 teaspoon blue powdered tempera paintFunnelWide-mouthed seasoned (that the funnel have the right to rest in)Coffee filterCups or containersWaterMeasuring cupWhat friend Do:

1. Mix the dry soil and also tempera repaint thoroughly. Location the funnel in the jar and place the coffee filter in the funnel. Pour the floor mixture into the funnel.

2. Gradually pour 1/2 cup water into the funnel, watching as the water runs out of the funnel into the jar. An alert the color of the water.

3. Eliminate the funnel from the jar and also pour the water into a cup or container. Change the funnel over the jar, through the coffee filter complete of sand quiet in place.

4. Repeat procedures 2 and 3 through a new 1/2 cup the water numerous times, saving the water in a new cup after each pouring.

What Happens:

You’ll notice that once the an initial half cup of water went with the soil, it come out together a really dark blue color. However, the water came out lighter with each extr cup. Eventually, the water traveling through the soil come out clear in the jar. Did you count exactly how many fifty percent cups of water it took to make the water run clear?

The tempura repaint in this experiment represents the nutrients and also dissolved particles found in the soil. Water is a really efficient transporter of particles as shown by the color of water together it was poured v the soil. The soil started with a reasonably high lot of nutrients and also particles in the – the tempura paint. The water flowing v the soil was able to pick increase a large proportion of the “nutrients” and carry them with it with the funnel. Every subsequent pouring of water picked up more nutrients. With each pouring, the continuing to be nutrients became less and also less till the water ran clear and there to be no much more nutrients left come travel through the water.

Noteworthy Scientist: George Gabriel Stokes, 1819-1903

George Gabriel Stokes was an accomplished British mathematician in the 19th Century, however throughout his career, he emphasized the importance of experimentation and problem solving rather than focusing exclusively on mathematics.

By experimenting and applying math to physics, Stokes come up with a legislation that describes the movement of a solid v a fluid or a gas. Recognized as Stoke’s Law, this legislation of viscosity developed the science of hydrodynamics. Stoke’s Law explains cloud motion, wave motion, and also the resistance the water to delivery movement.

Most the Stoke’s occupational revolved approximately waves (sound, light, and also water) and how they move through various mediums, such together water and gas. The experimented with how wind affects the strongness of a sound and also how the intensity is affected by the type of gas the sound waves travel through. The named and also explained fluorescence and also investigated the wave concept of light. He additionally worked on understanding the different colored bands that could be viewed in a spectrum and also made significant contributions come what we know around light and also optics.

Stokes is often contrasted to sir Isaac Newton since there are numerous parallels between Stoke’s life and also Newton’s life: both had breakthrough discoveries, arisen laws that motion, investigated light and optics, organized the same prestigious Lucasian Chair of math at the college of Cambridge, and also served in Parliament.

Fabulous Facts


Most gemstones contain several elements. The exception? The diamond. It’s every carbon.

Which of the 50 states has never had an earthquake? phibìc Dakota.

The Earth’s equatorial circumference (40,075 km) is better than the polar circumference (40,008 km).

The earth is estimated to sweet 6.6 sextillion tons, or 5.97 x 1024 kg. Come compare, a million is a 1 v 6 zeros complying with it – a sextillion is a 1 with 21 zeros following it. (1,000,000,000,000,000,000,000)


An inch of rain water is tantamount to 15 inch of dry, powdery snow.

The deepest part of the s is 35,813 feet (10,916 meters) deep and occurs in the Mariana Trench in the Pacific Ocean. At the depth the press is 18,000 pounds (9172 kilograms) per square inch.

The human mind is 80% water.


8-12 miles over the earth, rivers that air recognized as jet streams move above us. Number of miles wide and 1-2 miles deep, this currents the air have the right to have wind speeds together high together 250 miles every hour. Come contrast, the the strongest hurricanes have actually wind speeds in between 150-200 miles every hour.


A bolt of lightning is about 5,000 °F (~2,800 °C).

The facility of the sunlight is around 27 million levels Fahrenheit (15 million °C).

Elements combined

When hydrogen burns in the air, water is formed.

Oxygen is the most abundant facet in the Earth’s crust, waters, and atmosphere (about 49.5%).

Sound travels around 4 times faster in water than in air.

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Wind and water both cause erosion to the earth, moving large amounts the sand and rock come tear down mountains and also build brand-new structures.