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Like solids and liquids, gas is a common state of matter.
Pure gases are made up of just one atom. Neon is an example of a pure gas.
Elemental gases are made up of two or more of the same atoms joined together. Hydrogen gas (H2) is an example an elemental gas.
Compound gases contain a combination of different atoms. Carbon monoxide (CO) is an example of a compound gas.
The air we breathe here on Earth is made up of different gases. It contains around 78% nitrogen, 21% oxygen, 1% argon and a small amount of other gases.
Natural gas contains mostly methane, it is used as a fuel to generate electricity and is common in the home where it can be used for heating, cooking and other purposes.
Gas pressure is measured in pascals.
The helium balloons you get at parties and carnivals float because helium is lighter than the air surrounding it.
Noble gases are a group of chemical elements that are very stable under normal conditions. Naturally occurring noble gases include helium, neon, argon, krypton, xenon and radon.
The ozone layer that protects Earth from the Sun’s potentially damaging UV light is made up of ozone (O3), an oxygen allotrope containing 3 oxygen atoms bound together.
Nitrous oxide (N20) is a gas with interesting properties that allow it to be used in a variety of different ways, these include as an anesthetic in hospitals (you may have heard it referred to as laughing gas) and to increase the power of engines in motor racing (often called nitrous or just NOS).


Gas Facts:

-The first person to see a live cell with a microscope was Antoine van Leeuwenhoek, in 1674.
-Ecology is the study of ecosystems and how organisms interact with their environment.
-While some bacteria can make you sick, others have positive benefits such as helping you digest food or even make yogurt.
-Molds, yeasts and mushrooms are types of fungus.
-The common cold is a type of virus.
-Viruses can be treated with antiviral drugs.
-Bacteria are extremely small and are made up of just one cell.
-Bacterial infections can be treated with antibiotics.
-When the DNA of an organism changes and results in a new trait (characteristic) it is known as mutation.
-French chemist and microbiologist Louis Pasteur was well known for inventing a process to stop various foods and liquids making people sick. Called Pasteurization, it reduces the amount of microorganisms that could lead to disease without having a noticeable effect on taste and quality in a way which methods such as sterilization might.

Louis Pasteur Facts:
-Louis Pasteur was a French chemist and microbiologist who made many important discoveries related to the immune system, vaccinations, chemistry and the nature of diseases.
-Louis Pasteur lived from December the 27th 1822 to September the 28th 1895 and was famous for his work on disease causes and prevention.
-He is well known for inventing a process to stop food and liquid such as milk from making people sick. This method is called Pasteurization, it helps reduce the number of microorganisms that could cause disease while not affecting the quality and taste in a way which sterilization would.
-Many of Pasteur’s experiments supported the germ theory of disease, they helped show that microorganisms are the true cause of many diseases. In earlier times people believed that diseases were spontaneously generated, over time this theory was superseded thanks to the work of Pasteur and many others.
-Pasteur’s work also included breakthroughs in the field of chemistry. He discovered the molecular basis for the asymmetry of certain crystals, made discoveries related to the nature of tartaric acid and was the professor of chemistry at the University of Strasbourg.
-Pasteur studied the immune system and vaccination through research on chicken cholera and other diseases. He helped produce the first vaccine for rabies, saving the life of a young boy in 1885 who became the first person to receive such treatment.
-In honor of his work and influential contributions, Pasteur was made a Grand Croix of the Legion of Honor, a prestigious French order.
-Famous Louis Pasteur quotes include: “Science knows no country, because knowledge belongs to humanity, and is the torch which illuminates the world.”
-“I am on the edge of mysteries and the veil is getting thinner and thinner.”
-“I am utterly convinced that Science and Peace will triumph over Ignorance and War, that nations will eventually unite not to destroy but to edify, and that the future will belong to those who have done the most for the sake of suffering humanity.”
-“One does not ask of one who suffers: What is your country and what is your religion? One merely says: You suffer, that is enough for me”


Food Facts:
McDonald’s fast food chains employ over 1.5 million people around the world. More fast food facts.
Different parts of the world have their own local cuisine. The diets and general food habits of various cultures depend on social, religious, economic and safety factors as well as the availability of different foods.
Examples of food and cuisine that are popular or famous in certain areas of the world include hummus in the Middle East, apple pie in the USA, raw fish in Japan, cheese in France, roast meat and vegetables in England, curry in India and tortillas in Mexico.
There are around 2000 different plant types that humans use to cultivate food.
Examples of popular vegetables include lettuce, carrots, asparagus, cauliflower, broccoli, spinach, potatoes and onions.
The sweet potato is a root vegetable and is not closely related to the potato. More potato facts.
Cutting onions releases a gas which causes a stinging sensation when it comes into contact with your eyes. Your body produces tears to dilute the irritant and remove it from your eyes.
Pumpkins are usually labelled as vegetables but they contain seeds and are technically fruit. More pumpkin facts.
China is the largest producer of garlic, producing over 10 million tons in 2008 and accounting for over 75% of world output.
Examples of popular fruits include apples, oranges, pears, strawberries, peaches, bananas, apricots and grapes.
Technically speaking, strawberries aren't even berries! Read our strawberry facts to learn more.
The average apple contains around 130 calories. More apple facts.
India is the world’s largest producer of bananas, producing nearly 22 million tons in 2007. More banana facts.
Humans use many different methods for gathering food which include farming, hunting, gardening, foraging and fishing.
Humans eat meat from a number of different animals, common examples include meat from chickens, cows, sheep and pigs. Other food products that come from animals include milk, eggs and honey.
Although humans are omnivores (eating both plants and animals), many people choose not to eat meat and fish, they are known as vegetarians. Those who don’t eat or use any products made from animals (including eggs, dairy products and honey) are known as vegans.
Food for human consumption is typically made from plants and animals but we also eat other products such as fermented foods and fungus (mushrooms, truffles etc).
Cooking is an important part of food preparation that involves applying heat. In most cases this transforms the chemical make up of food, altering its texture, flavor, nutritional properties and appearance.
Types of equipment used in the cooking process include ovens, microwaves, toasters, grills, pots and frying pans.
Various cooking methods include boiling, simmering, steaming, sauteing, pan frying and deep-frying.
Around 70 million people suffer from food poisoning every year with around 7 million of these cases being fatal. Careful food storage, temperature control and preparation is necessary to avoid potentially dangerous bacteria, toxins and viruses.
Around 8% of children and 2% of adults have some kind of food allergy, this occurs when the body’s immune system incorrectly assumes a certain food protein is harmful and attacks it. Common examples of food allergies include reactions to peanuts, gluten and shellfish. 


Water Facts:
-Water is made up of two elements, hydrogen and oxygen. Its chemical formula is H2O.
-Each molecule of water is made up of two hydrogen atoms bonded to a single oxygen atom.
-The existence of water is essential for life on Earth.
-Water has three different states, liquid, solid and gas.
-The word water usually refers to water in its liquid state. The solid state of water is known as ice while the gas state of water is known as steam or water vapor.
Water covers around 70% of the Earth’s surface.
-The three largest oceans on Earth are the Pacific Ocean (largest), the Atlantic Ocean (second largest) and the Indian Ocean (third largest). More ocean facts.
-Found in the Pacific Ocean, the Mariana Trench is the deepest known point in the world’s oceans.
-Ocean tides are caused by the rotation of the Earth and the gravitational pull of the Moon and Sun acting on ocean water.
-Water from a sea or ocean is known as seawater. On average, every kilogram (2.2lb) of seawater contains around 35 grams (1.2 oz) of dissolved salt.
-The freezing point of water lowers as the amount of salt dissolved in at increases. With average levels of salt, seawater freezes at -2 °C (28.4 °F).
-The longest river in the world is the Nile River, it reaches 6650 kilometers in length (4132 miles).
-The second longest river in the world is the Amazon River, it reaches 6400 kilometers (4000 miles) in length.
-The longest river in the USA is the Missouri River. At around 2,340 miles (3,770 km) in length it is slightly longer than the Mississippi River (2,320 miles). The two combine to form the longest river system in North America.
-Water makes a good solvent with many sugar, salts and acids easily dissolving in it. On the other hand oils and fats don’t mix well with water.
-The water cycle involves water evaporating (turning into a gas), rising to the sky, cooling and condensing into tiny drops of water or ice crystals that we see as clouds, falling back to Earth as rain, snow or hail before evaporating again and continuing the cycle. Learn more about the water cycle.
-Water in the form of ice is found at the polar ice caps of the planet Mars, some scientists have also suggested the possibility of liquid water on the red planet.
-Pure water has no smell and no taste, it also has a pH level around 7.
-While most people know that water boils at 100 °C (212 °F), this is at the normal conditions of sea level. The boiling point of water actually changes relative to the barometric pressure. For example, water boils at just 68 °C (154 °F) on the top of Mount Everest while water deep in the ocean near geothermal vents can remain in liquid form at temperatures much higher than 100 °C (212 °F).
-Water expands as it cools from 4 °C to 0 °C (above 4 °C it does the opposite). In freezing conditions, water has been known to burst water pipes as it freezes to ice.
-Water can move up narrow tubes against the force of gravity in what is known as capillary action. Check out this capillary action experiment for more.
-Most people around the world have access to clean drinking water but it is a major problem in poorer areas of the world. Water pollution and low quality water can lead to dangerous bacteria, disease and viruses such as E coli and Cryptosporidium.
-Drinking water is needed for humans to avoid dehydration, the amount you need each day depends on the temperature, how much activity you are involved in and other factors.
-An important use for water is in agricultural irrigation, this is when water is artificially added to soil in order to assist the growth of crops.
-Water is used frequently by firefighters to extinguish fires. Helicopters sometimes drop large amount of water on wildfires and bush fires to stop fires spreading and limit the damage they can cause.
-The water industry helps deliver water to homes in various cities and countries around the world. This can involve services such as purification, sewage treatment, filtering, distillation and plumbing.
-Electricity can be created from hydro power, a process that uses water to drive water turbines connected to generators. There are many hydroelectric power stations around the world.
-Water also plays a role in cooking. Steaming and boiling food are well known cooking methods. You may have noticed this last time you made pasta or noodles.
-Water is also used for fun. Water sports are a very popular recreational activity and include things like swimming, surfing and water skiing. Ice and snow is also used in ice skating, ice hockey, skiing and snowboarding.


Chemistry Facts:
-Hydrogen is the first element on the periodic table. It has an atomic number of 1. It is highly flammable and is the most common element found in our universe.
Liquid nitrogen boils at 77 kelvin (−196 °C, −321 °F).
-Around 1% of the sun’s mass is oxygen.
-Helium is lighter than the air around us so it floats, that's why it is perfect for the balloons you get at parties.
-Carbon comes in a number of different forms (allotropes), these include diamond, graphite and impure forms such as coal.
-Under normal conditions, oil and water do not mix. More oil facts.
-Although it is still debated, it is largely recognized that the word 'chemistry' comes from an Egyptian word meaning 'earth'.
-The use of various forms of chemistry is believed to go back as long ago as the Ancient Egyptians. By 1000 BC civilizations were using more complex forms of chemistry such as using plants for medicine, extracting metal from ores, fermenting wine and making cosmetics.
-Things invisible to the human eye can often be seen under UV light, which comes in handy for both scientists and detectives.
-Humans breathe out carbon dioxide (CO2). Using energy from sunlight, plants convert carbon dioxide into food during a process called photosynthesis.
-Chemical reactions occur all the time, including through everyday activities such as cooking.
-Try adding an acid such as vinegar to a base such as baking soda and see what happens!
-Above 4 °C, water expands when heated and contracts when cooled. But between 4 °C and 0 °C it does the opposite, contracting when heated and expanding when cooled. Stronger hydrogen and oxygen bonds are formed as the water crystallizes into ice. By the time it's frozen it takes up around 9% more space.
-Often formed under intense pressure over time, a crystal is made up of molecules or atoms that are repeated in a three dimensional repeating pattern. Quartz is a well known example of a crystal.
-Athletes at the Olympic Games have to be careful how much coffee they drink. The caffeine in coffee is a banned substance because it can enhance performance. One or two cups are fine but they can go over the limit with more than five. (update - as of 2004 caffeine has been taken back off the WADA banned list but its use will be closely monitored to prevent future abuse by athletes.)


Gravity Facts:

-Because of differences in gravity, a 200 pound person would only weigh 76 pounds on Mars. More gravity facts.
-Electric eels can stun both predators and prey with electric shocks of around 500 volts. More electricity facts.
-Energy from food is usually measured in joules or calories. More energy facts.
-Light from the Earth takes just 1.255 seconds to reach the Moon. More light facts.
-Sound travels at a speed of around 767 miles per hour (1,230 kilometers per hour). More sound facts.
-When traveling at 80 kilometers per hour (50 miles per hour), cars use around half of their fuel just to overcome wind resistance.
-Water can work against gravity, moving up narrow tubes in a process called capillary action.
-A magnifying glass uses the properties of a convex shaped lens to magnify an image, making it easier to see.
-A scientist who studies physics is known as a physicist.
-Uranus is the only planet in our solar system that rolls on its side like a barrel, while Venus is the only planet that spins in the opposite direction to Earth.
-The fastest land animal in the world is the Cheetah, clocking a max speed of around 113 km per hour (70 mph).
-1921 Nobel Prize in Physics was won by Albert Einstein for his work in the field of theoretical physics.

Sound Facts:
-Sound comes from vibrations. These vibrations create sound waves which move through mediums such as air and water before reaching our ears.
-Our ears vibrate in a similar way to the original source of the vibration, allowing us to hear many different sounds.
-Dogs can hear sound at a higher frequency than humans, allowing them to hear noises that we can’t.
-Sound is used by many animals to detect danger, warning them of possible attacks before they happen.
-Sound can’t travel through a vacuum (an area empty of matter).
-The speed of sound is around 767 miles per hour (1,230 kilometres per hour).
-The loud noise you create by cracking a whip occurs because the tip is moving so fast it breaks the speed of sound!
-When traveling through water, sound moves around four times faster than when it travels through air.
-The scientific study of sound waves is known as acoustics.
-Although music can be hard to define, it is often described as a pleasing or meaningful arrangement of sounds.
-The sound of thunder is produced by rapidly heated air surrounding lightning which expands faster than the speed of sound.


Earth Facts:
-Magma is the hot liquid rock under the surface of the Earth, it is known as lava after it comes out of a volcano.
-Natural gas doesn't have an odor, strong smells are added to it by humans so it can be detected when there are leaks.
-Hawaii is moving towards Japan at the speed of 10cm a year. This is because they are on different tectonic plates.
-The world's largest desert (outside of the polar regions) is the Sahara, it covers about one third of Africa!
-Stretching out to an impressive length of 6696 kilometers (4160 miles) long, the Nile River is the longest river on earth.
-The volcanic rock known as pumice is the only rock that can float in water.
-Mt Everest is the highest mountain on earth, its peak reaches 8,848 meters (29029 feet) above sea level. Check out the highest mountains on each continent of the Earth.
-On average the Atlantic Ocean is the saltiest of Earth’s major oceans.
-Earthquakes that occur out at sea can cause huge tsunamis capable of reaching land and endangering people.
-Metamorphic rocks are formed by extreme pressure and heat. Read more about metamorphic, igneous and sedimentary rocks, find information on rocks and minerals or check out our interesting fossil facts.
-The Earth isn't perfectly round, it is slightly flattened at the north and south poles. Learn about the polar regions with our Antarctica facts and Arctic facts.
-Scared of the Bermuda Triangle? Despite its reputation it is actually part of a commonly sailed shipping route.
-Scientists have the dated the Earth as being between 4 and 5 billion years old!
-The Amazon rain forest is the largest tropical rain forest on Earth. Enjoy more rain forest facts or learn about jungles.
-Talc is the softest mineral found on Earth, reaching just 1 on Mohs scale of hardness, it is often used to make talcum powder.
-The Great Barrier Reef in Australia is the largest living structure in the world.
-The Niagara Falls are located on the border of the USA and Canada.
-Rock found at the bottom of the Grand Canyon is around 2 billion years old.
Although earthquakes can be deadly, most are very small and not even felt by humans.


Space Facts:
-The Sun is over 300000 times larger than earth. More Sun facts.
-Halley’s Comet was last seen in the inner Solar System in 1986, it will be visible again from Earth sometime in 2061 (get your camera ready). More comet facts.
-Venus is the hottest planet in our solar system with a surface temperature of over 450 degrees Celsius.
-Many scientists believe that an asteroid impact caused the extinction of the dinosaurs around 65 million years ago. More asteroid facts.
-The Solar System formed around 4.6 billion years ago. More Solar System facts.
-The Moon appears to have more craters and scars than Earth because it has a lot less natural activity going on, the Earth is constantly reforming its surface through earthquakes, erosion, rain, wind and plants growing on the surface, while the moon has very little weather to alter its appearance. More Moon facts.
-Saturn isn't the only ringed planet, other gas giants such as Jupiter, Uranus and Neptune also have rings, they are just less obvious.
-Footprints and tire tracks left behind by astronauts on the moon will stay there forever as there is no wind to blow them away.
-In 2006, astronomers changed the definition of a planet. This means that Pluto is now referred to as a dwarf planet. Learn more dwarf planet facts.
-Because of lower gravity, a person who weighs 200 pounds on earth would only weigh 76 pounds on the surface of Mars.
-The only planet that rotates on its side like a barrel is Uranus. The only planet that spins backwards relative to the others is Venus.
-Some of the fastest meteoroids can travel through the solar system at a speed of around 42 kilometres per second (26 miles per second). Check out more meteoroid facts or learn the difference between comets, asteroids and meteoroids.
-The first man made object sent into space was in 1957 when the Russian satellite named Sputnik was launched.
-Jupiter's 4 biggest moons are named Europa, Ganymede, Callisto and Io. More Solar System moon facts.
-It is because of the Sun & Moons gravity that we have high & low tides.
-For a list of important space definitions take a look at our glossary of easy space and astronomy definitions for kids.


Human Body Facts:
-The brain uses over a quarter of the oxygen used by the human body.
-Your heart beats around 100000 times a day, 36500000 times a year and over a billion times if you live beyond 30.
-Red blood cells carry oxygen around the body. They are created inside the bone marrow of your bones.
-The color of a humans skin is determined by the level of pigment melanin that the body produces. Those with small amounts of melanin have light skin while those with large amounts have dark skin.
-Adult lungs have a surface area of around 70 square metres!
-Humans have a stage of sleep that features rapid eye movement (REM). REM sleep makes up around 25% of total sleep time and is often when you have your most vivid dreams.
-Most adults have 32 teeth.
-The smallest bone found in the human body is located in the middle ear. The stapes (or stirrup) bone is only 2.8 millimetres long.
-Your nose and ears continue growing throughout your entire life.
-Infants blink only once or twice a minute while adults average around 10.
-As well as having unique fingerprints, humans also have unique tongue prints.
-The left side of your body is controlled by the right side of your brain while the right side of your body is controlled by the left side of your brain.
-Antibiotics are only effective against bacteria, they won't help in fighting off a virus.
-It takes the body around 12 hours to completely digest eaten food.
-Your sense of smell is around 10000 times more sensitive than your sense of taste.


Fire Facts:
-Fire is a chemical reaction that releases light and heat.
-Substances combine with oxygen in the air, combusting with a flame and often smoke.
-Fires require fuel, oxygen and heat to burn.
-Different types of fuel include coal, oil and wood.
-Flames are the part of a fire which we can see, they can be different colors, depending on the substance which is burning.
-A candle flame typically burns at around 1000 degrees Celsius (1800 Fahrenheit).
-Fire is very dangerous to humans as it can easily burn or blister skin. It is important to take safety precautions when using fire.
-Fire is also very useful to humans for lighting, heating, cooking and more.
-Scientists believe that humans began using fire to cook food in a controlled way around 1 million years ago.
-Forest fires can be extremely destructive and are dangerous to both humans and wildlife.
-Fires are also an important ecological process that can stimulate growth.
-Fires can be stopped in 3 different ways:
Removing the fuel source by exhausting it or taking it away.
-Removing the oxygen by smothering the fire.
-Removing the heat by absorbing it with water.
-Fire extinguishers are often used to control fires by discharging water, foams, carbon dioxide, dry chemicals or other substances.


Electricity Facts:

-Modern society relies heavily on the convenience and versatility of electricity. It powers your microwave, helps light your house, lets you watch TV and so much more.
-Electric current is measured in amperes (amps).
-Electric potential energy is measured in volts.
-Two positive charges repel each other, as do two negative charges. Opposite charges on the other hand attract each other.
-When an electric charge builds up on the surface of an object it creates static electricity. You have probably experienced static electricity in the form of a small electric shock, which is what happens when the electric charge is quickly neutralized by an opposite charge.
-Electric eels can produce strong electric shocks of around 500 volts for both self defense and hunting.
-Electric circuits can contain parts such as switches, transformers, resistors and transformers.
-A common way to produce electricity is by hydropower, a process that generates electricity by using water to spin turbines attached to generators.
-The world’s biggest source of energy for producing electricity comes from coal. The burning of coal in furnaces heats boiler water until it becomes steam which then spins turbines attached to generators.
-Lightning is a discharge of electricity in the atmosphere. Lightning bolts can travel at around 210,000 kph (130,000 mph), while reaching nearly 30,000 °C (54,000 °F) in temperature.
-Electricity plays a role in the way your heart beats. Muscle cells in the heart are contracted by electricity going through the heart. Electrocardiogram (ECG) machines used in hospitals measure the electricity going through someone’s heart, when the person is healthy it usually shows a line moving across a screen with regular spikes as the heart beats.
-You may have heard of direct current (DC) and alternating current (AC). The difference between the two is in the way the electrons flow. In DC electrons move in a single direction while in AC they change directions, switching between backwards and forwards. The electricity use in your home is AC while DC comes from sources that include batteries.
-Back in the 1880’s there was even a ‘war of currents’ between Thomas Edison (who helped invent DC) and Nikola Tesla (who helped invent AC). Both wanted their system to be used with AC eventually winning out due to the fact that it is safer and can be used over longer distances.
-Electric fields work in a similar way to gravity with an important exception being that while gravity always attracts, electric fields can either attract or repulse.
-American Benjamin Franklin carried out extensive electricity research in the 18th century, inventing the lightning rod among his many discoveries. Lightning rods protect buildings in the event of lightning by conducting lightning strikes through a grounded wire.


Nuclear Facts:
-The word ‘nuclear’ is related to the nucleus of an atom, it is often used to describe the energy produced when a nucleus is split (fission) or joined with another (fusion).
-The nucleus is positively charged and found at the central core of an atom.
-Nuclear physics is the study of atomic nuclei and their interactions.
-Nuclear power uses fission to create heat and electricity.
-The US, France and Japan are the largest producers of nuclear power.
-Nuclear power provides around 14% of the world’s electricity.
-Nuclear power plants have a relatively good safety record but there is ongoing debate into the threat they pose, especially after widely publicized accidents at Chernobyl, Three Mile Island and Fukushima.
-The radioactive waste produced by nuclear reactors can be difficult to dispose of safely.
-The military often use nuclear reactors to power their submarines and aircraft carriers. Learn more about atomic energy with our nuclear power facts.
-Nuclear weapons use the energy produced by fission or fusion to create destructive blasts.
-While many nuclear weapons have been used in testing, only 2 have been used as part of warfare.
-In August 1945, near the end of World War 2, the United States used atomic bombs on the Japanese cities of Hiroshima and Nagasaki, leading to the death of approximately 200000 people.
-Enriched uranium is a crucial element of both nuclear weapons and nuclear power production.
-The Sun creates energy through the nuclear fusion of hydrogen nuclei into helium.
-It is believed that radiation exposure led to the death of Marie Curie in 1934.


Metal Facts:

-Metals are usually solid, good conductors of electricity and heat, shiny when clean, strong and malleable (meaning they can be bent and shaped).
-Gold is shiny and doesn’t corrode, this means it is a great metal for making jewelry.
-The chemical symbol used for silver is Ag, this comes from the Latin word for silver, argentum.
-While aluminum is the most common metal found in the Earth's crust, the most common metal found on Earth is iron, mostly because it makes up such a large part of the Earth's core.
-Copper is a good conductor of electricity and is often used for making wires.
-At room temperature, mercury is the only metal that is in liquid form.
-Aluminum is a good conductor of heat and is often used to make cooking pots.
-Alkali metals such as sodium, potassium, rubidium, cesium and francium are extremely reactive elements, just putting them in water can result in an explosion! They are carefully stored in oil to prevent this happening. -
-Tungsten has a very high melting point, after carbon it has the second highest melting point of all elements.
-Metals are strong and are useful for making tools, buildings, bridges and other structures where strength is important.
-Steel is an important alloy (combination of metals) that is created from a mixture of metals, mostly iron. There are many different types of steel including stainless steel, galvanized steel and carbon steel. Steel is commonly used to make a number of products including knives, machines, train rails, cars, motors and wires.
-Bronze is a metal alloy made from copper and tin. Copper makes up the larger amount, usually between 80 to 95%.


Plant Facts:

-Tree resin which has been fossilized is known as amber, it sometimes contains plant material or small animals that were trapped inside. More tree facts for kids.
-Some plants are carnivores, gaining nutrients by eating various small insects and spiders. A well known example of a carnivorous plant is the Venus Flytrap.
-Bamboo can be a fast growing plant, some types can grow almost a metre (3.28 feet) in just one day!
-While using energy from sunlight, plants turn carbon dioxide into food in a process called photosynthesis.
-Around 2000 different types of plants are used by humans to make food.
-Onions might taste good but they can be painful to chop. A gas is released when you cut onions that irritates you eyes, the tears you produce while this happens are your body’s way of washing it from your eyes.
-In the agricultural industry, to ensure crops of food grow well water is often added to soil in the form of irrigation.
-Plant matter found at the bottom of areas with water such as swamps can eventually turn into coal due to a process called metamorphosis (changing form).
-There are over 200,000 identified plant species and the list is growing all the time.
-Poison ivy produces a skin irritant called urushiol. Touching poison ivy will cause an allergic reaction, usually in the form of an itchy rash on the skin.
-Fertilizers are chemicals added to plants to help them grow. Important elements in fertilizers include nitrogen, phosphorus and potassium. Manure (animal waste) is also used as a fertilizer.


Light Facts:

-In physics, light refers to electromagnetic radiation. The light we normally talk about in everyday life refers to the visible spectrum (the part of the electromagnetic spectrum that the human eye can see).
-Other animals can see parts of the spectrum that humans can’t. For example, a large number of insects can see ultraviolet (UV) light.
-UV light can be used to show things the human eye can’t see, coming in handy for forensic scientists.
-The wavelength of infrared light is too long to be visible to the human eye.
-Scientists study the properties and behaviors of light in a branch of physics known as optics.
-Isaac Newton observed that a thin beam of sunlight hitting a glass prism on an angle creates a band of visible colors that includes red, orange, yellow, green, blue, indigo and violet (ROYGBIV). This occurred because different colors travel through glass (and other mediums) at different speeds, causing them to refract at different angles and separate from each other.
-Light travels very, very fast. The speed of light in a vacuum (an area empty of matter) is around 186,000 miles per second (300,000 kilometres per second).
-Light travels slower through different mediums such as glass, water and air. These mediums are given a refractive index to describe by how much they slow the movement of light. Glass has a refractive index of 1.5, meaning that lights travels through it at around 124,000 miles per second (200,000 kilometres per second). The refractive index of water is 1.3 while the refractive index of air is 1.0003, meaning that air only slightly slows down light.
-Light takes 1.255 seconds to get from the Earth to the Moon.
-Sunlight can reach a depth of around 80 metres (262 feet) in the ocean.
-One of the many things Italian scientist Galileo Galilee worked on was telescopes, producing telescopes with around 30x magnification in some of his later work. These telescopes helped him discover the four largest moons orbiting Jupiter (later named the Galilean satellites).


Energy Facts:

-The word energy comes from the Greek word energeia.
-Most types of energy are either a form of kinetic energy or potential energy.
-Common examples include heat energy, elastic potential energy, chemical energy, sound energy, nuclear energy, geothermal energy and gravitational potential energy.
-Kinetic energy refers to the energy an object has because of its movement. A car in motion has kinetic energy, as does a basketball when you pass or shoot it.
-Energy can be transformed from one form to another. In lightning, electric potential energy transforms into light, heat and sound energy.
-The law of conservation of energy states that energy can only be transformed, it can’t be created or destroyed.
-You might have heard of Albert Einstein’s famous formula E = mc² (energy equals mass multiplied by the speed of light squared).
-Food contains chemical energy which is used by living organisms such as animals to grow and reproduce. Food energy is usually measured in calories or joules.
-Wind farms contain large numbers of wind turbines which are used to transform wind energy into a useful energy such as electricity. The use of wind power to generate electricity doubled between the years 2005 and 2008.
-The USA's Mojave Desert is home to the world's largest solar power plant.
-The Three Gorges Dam in China is the world's largest hydroelectric power station.
-Nuclear power produces around 13% of the world's electricity. More nuclear power facts.
-Plants use energy from sunlight during an important process called photosynthesis.
-A person standing on a diving board above a swimming pool has gravitational potential energy.
-During chemical reactions, chemical energy is often transformed into light or heat.
-Stretched rubber bands and compressed springs are examples of elastic potential energy.

-Photosynthesis is a process that involves plants using energy from sunlight to convert carbon dioxide into food.


Magnet Facts:

-Magnets are objects that produce an area of magnetic force called a magnetic field.
-Magnetic fields by themselves are invisible to the human eye.
-Iron filings can be used to show magnetic fields created by magnets.
-Magnets only attract certain types of metals, other materials such as glass, plastic and wood aren't attracted.
-Metals such as iron, nickel and cobalt are attracted to magnets.
-Most metals however are not attracted to magnets, these include copper, silver, gold, magnesium, platinum, aluminium and more. They may however magnetize a small amount while placed in a magnetic field.
-Magnetism can attract magnetic objects or push them away.
-Magnets have a magnetic north pole and a magnetic south pole. If the same pole of two magnets are placed near each other they will push away (repel), while if different poles are placed near each other they will pull together (attract).
-Magnetic objects must be inside the magnetic field to respond, which is why you may have to move a magnet closer for it to have an effect.
-The Earth's core is believed to be a mix (alloy) of iron and nickel, giving the Earth its own magnetic field.
-The Earth's magnetic field is responsible for deflecting the solar wind, charged particles that come from the Sun.
-Magnetic compasses use the Earth's magnetic field to help navigate in north, south, east and west directions.
-Electromagnets are created by an electric current running through a surrounding coil. They have many uses including the generation of electricity in hydroelectric dams.


Flight Facts:

-While birds have been flying for millions of years, it's something relatively new to humans and we rely on some important scientific principles to achieve it.
-Beginning with simple kites, humans have moved on to develop gliders, airships, helicopters, commercial planes and even supersonic flight.
-Supersonic flight (breaking the sound barrier) is achieved when an object travels at a speed faster than sound (1235kph, 768mph).
-The Wright Brothers, Orville and Wilbur, were American aviation pioneers who created the first successful airplane, thanks in part to their invention of 3-axis control, enabling the pilot to effectively control the plane.
-While a number of flight pioneers were working on their own powered flight at the time (including New Zealand's Richard Pearse) the Wright Brothers are widely credited with the first controlled and sustained human flight on December 17, 1903.
-Planes have wings that feature an airfoil (aerofoil) shape, this is important as it helps overcome the effect of gravity pulling down on the plane.
-The wing creates lift as it moves through the air, a process that can be explained by Bernoulli's principle. Because of the airfoil shape, air flows faster over the top than the bottom, creating higher pressure underneath the wing which then pushes the plane up through the lower air pressure.
-Disturbed air and friction create drag as the plane moves forward, slowing it down.
-An engine provides thrust to move the plane forward at a speed great enough to overcome drag and allow the wings to create the lift necessary to fly.
-Airships and blimps are lighter than air and use buoyancy for flight. They are typically filled with gas (such as helium) that is less dense than the surrounding atmosphere.
-The only living things capable of powered flight are insects, birds and bats.
-While some can glide, bats are the only mammals that can achieve sustained level flight.
-Flying fish have been known to glide for hundreds of metres thanks to enlarged fins that act like wings.


Time Facts:

-We use time to order events in the past, present and future. We also use it to make comparisons and measure the speed at which things move.
-If you wanted to measure time you could use a watch, clock, hourglass or even a sundial.
-A sundial is a tool that uses the position of the Sun to measure time, typically involving a shadow cast across a marked surface.
-The use of pendulums to accurately measure time was discovered by Galileo Galilei around 400 years ago. A pendulum is a free swinging weight hanging from a pivot.
-There are 60 seconds in a minute, 60 minutes in an hour and 24 hours in a day.
-Normal years have 365 days but a Leap year has 366. The Earth takes a little longer than 365 days to go around the Sun so we add an extra day in February every four years (with a few exceptions) to keep calendars and seasons aligned.
-10 years is known as a decade, 100 years is known as a century and 1000 years is known as a millennium.
-Milliseconds, microseconds and nanoseconds are examples of very small units of time.
-Planck time is the name given to the smallest known unit of time. It’s a little confusing but it measures the amount of time it takes light to travel 1 Planck length (a distance so small that it can’t even be measured!).
-Scientists believe the moon was used as a form of calendar as far back as 6000 years ago. Calendars have been changing ever since and are very accurate in modern times.
-Accurate clocks that measure hours, minutes and seconds have improved with the invention of sundials, water clocks, mechanical clocks, pendulums and hourglasses through to the digital displays and atomic clocks of today.
-Many places use daylight saving time (typically by putting clocks forward an hour) for longer daylight in the evenings.
-Different parts of the world are located in different time zones. This means that while you are having breakfast in the morning, someone in another part of the world is having dinner.
-Theories related to time have been put forward by famous scientists such as Isaac Newton and Albert Einstein. You may have even heard of the term ‘spacetime’, a model in physics that joins space and time together.
-In terms of philosophy, time is difficult to define. Scientists and philosophers have disagreed on our understanding of time for many years. Some argue it is a ‘real’ part of the Universe while others argue it is just the way humans think, comparing events and putting them in sequence. It’s a little confusing but fun to think about, what do you think?
-Some more questions to get your brain buzzing: Does time have a direction? Did it begin with the Big Bang? Is time travel possible?


Dinosaur Facts:

-The word dinosaur comes from the Greek language and means ‘terrible lizard’. The word was coined by English paleontologist Richard Owen in 1842 and was meant to refer to Dinosaurs impressive size rather than their scary appearance.
-Dinosaurs ruled the Earth for over 160 million years, from the Triassic period around 230 million years ago through the Jurassic period and until the end of the Cretaceous period around 65 million years ago.
-The time period from 250 million years ago until around 65 million years ago is known as the Mesozoic Era. It is often referred to as the Age of the Dinosaurs because most dinosaurs developed and became extinct during this time.
-It is believed that dinosaurs lived on Earth until around 65 million years ago when a mass extinction occurred.
-Scientists believe that the event leading to the extinction may have been a massive asteroid impact or huge volcanic activity. Events such as these could have blocked out sunlight and significantly changed the Earth’s ecology.
-The first dinosaur to be formally named was the Megalosaurus, back in 1824.
-A person who studies dinosaurs is known as a paleontologist.
-Rather than being carnivores (meat eaters), the largest dinosaurs such as the Brachiosaurus and Apatosaurus were actually herbivores (plant eaters).
-To help fight meat eaters such as the Allosaurus or Spinosaurus, many plant eaters had natural weapons at their disposal. Examples of this include the spikes on the tail of the Stegosaurus and the three horns attached to the front of the Triceratops’s head shield.
-Pterodactyls are not dinosaurs, they were flying reptiles that lived during the age of dinosaurs but by definition they do not fall into the same category. The same goes for water based reptiles such as Plesiosaurs.
-Birds descended from a type of dinosaurs known as theropods.
-Despite being long extinct, dinosaurs are frequently featured in the media. One of the more memorable examples of this is Michael Crichton’s 1990 book Jurassic Park. Adapted to movie in 1993, the story features cloned dinosaurs brought to life with the help of DNA found in mosquitoes trapped in amber.


Weather Facts:

-The highest temperature ever recorded in Antarctica is 14.6 °C (59 °F), recorded on January 5, 1974.
-The most rainfall ever recorded in 24 hours is 182.5 centimetres (71.9 inches) in Foc-Foc, La Réunion, during tropical cyclone Denise on January 8, 1966.
-The most rainfall ever recorded in one year is 25.4 meters (1000 inches) in Cherrapunji, India.
-The highest snowfall ever recorded in a one year period was 31.1 meters (1224 inches) in Mount Rainier, Washington State, United States, between February 19, 1971 and February 18, 1972.
-The fastest wind speed ever recorded is 484±32 km/h (301±20 mph). This was a 3 second gust recorded by a Doppler on Wheels (DOW) radar unit in Oklahoma City on May 3, 1999.
-The heaviest hailstone ever recorded weighed 1.0 kg (2.25 lb) and landed in Gopalganj District, Bangladesh on April 14, 1986.
-Clouds can be categorized into a number of different types; these include cumulus, stratus and cirrus.
-The Earth experiences millions of lightning storms every year, they are incredible discharges of electricity from the atmosphere that can reach temperatures close to 54,000 °F (30,000 °C) and speeds of 60,000 m/s (130,000 mph).
-The USA has more tornadoes than any other country in the world, averaging around 1200 a year. This is due largely to its unique geography which forms an area in central USA called “Tornado Alley” which is frequently hit by tornadoes.
-Tropical cyclones (often referred to as hurricanes or typhoons) feature strong winds, driving rain, rough seas and areas of low atmospheric pressure. They frequently form in tropical areas of the globe and can do considerable damage to populated areas. Examples of this include the 1970 Bhola cyclone, Typhoon Nina which hit China in 1975 and more recently in 2005 when Hurricane Katrina which caused great devastation and loss of life when it hit southern parts of the USA.