science facts

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• Nitroglycerin is a liquid used to create explosives such as dynamite. It is often used in the demolition and construction industries as well as by the military.
  
• Nitric acid (HNO[SUB]3[/SUB]) is a strong acid often used in the production of fertilizers.
  
• Ammonia (NH[SUB]3[/SUB]) is another nitrogen compound commonly used in fertilizers.

 

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Oxygen Facts

• Oxygen is an element with the chemical symbol O and atomic number 8.
  
• Oxygen is a very reactive element that easily forms compounds such as oxides.
  

 

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• Under standard temperature and pressure conditions two oxygen atoms join to form dioxygen (O[SUB]2[/SUB]), a colorless, tasteless and odorless gas.
  
• Oxygen is essential to human life, it is found in the air we breathe and the water we drink (H[SUB]2[/SUB]0).
  

 

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• Oxygen makes up around 21% of the air you breathe. It is also the most common element in the Earth’s crust (around 47%) and the third most common element in the Universe (but far less than hydrogen and helium, the two most common).
  
• The large amount of oxygen on Earth is supported by the oxygen cycle which involves the movement of oxygen between the air, living things and the Earth’s crust. Photosynthesis (a process that converts carbon dioxide into organic compounds using sunlight) plays a major role in this cycle.
  

 

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• Ozone (O[SUB]3[/SUB]) is an allotrope (different form) of oxygen that combines three oxygen atoms together. While ground level ozone is an air pollutant, the ozone layer in the Earth’s upper atmosphere provides protection from the suns harmful rays by filtering UV light.
  
• The sun’s mass is made up of around 1% oxygen.
  

 

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• Between 1770 and 1780, Swedish pharmacist Carl Wilhelm Scheele, British clergyman Joseph Priestley and French chemist Antoine Laurent Lavoisier researched, documented and helped discover oxygen. The name oxygen was first used by Lavoisier in 1777.
  
• Oxygen therapy is used as a common medical treatment. You may have seen patients on TV or in real life using an oxygen mask or nasal cannula (a plastic tube that fits behind the ears and delivers oxygen through the nostrils).
  

 

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• Oxygen has a number of other practical uses such as smelting metal from ore, water treatment, as an oxidizer for rocket fuel and a number of other industrial, chemical and scientific applications.
  
• Concentrated oxygen promotes fast combustion. While a spark or heat is still needed to start a fire, having concentrated oxygen near various fuels can be very dangerous.
  

 

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Helium Facts:

• Helium is a chemical element with the symbol He and atomic number 2.
  
• Helium is a colorless, tasteless and odorless gas
  

 

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• Helium is the second most common element in the Universe (after hydrogen), making up around 24% of its mass.
  
• Helium is part of a group of chemical elements called noble gases, the other five that occur naturally are neon, argon, krypton, xenon and radon. Under normal conditions they share similar properties, including being less likely to participate in chemical reactions due to their outer shell of electrons being full. Helium is the second least reactive element after neon.
  

 

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• French and English astronomers Pierre Janssen and Norman Lockyer are jointly credited with discovering helium after spectral analysis of sunlight following a solar eclipse in 1868.
  
• The word helium comes from the Greek word meaning sun (helios). It was named by Lockyer and English chemist Edward Frankland.
  

 

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• The USA is the world’s largest supplier of helium, with many reserves found in large natural gas fields.
  
• The rate at which helium is currently being used by humans is much faster than the rate at which the reserves are being replenished. New technologies for obtaining or recycling helium are one way for gas companies to help slow this problem.
  

 

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• Because helium is lighter than air it is commonly used to fill airships, blimps and balloons. As it doesn’t burn or react with other chemicals, helium is relatively safe to use for this purpose.
  
• While hydrogen is 7% more buoyant than helium it has a much higher fire risk.
  

 

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• You might notice the helium balloon you got from the amusement park slowly falling to the ground after a few days, this happens as the helium gradually leaks from the balloon.
  
• Helium has a lifting force of around one gram per liter. A balloon that holds 10 liters of helium should therefore lift an object weighing 10 grams. Unfortunately you’ll need around 5000 of these balloons if you weigh around 50kgs and want to get off the ground.
  

 

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• The balloon boy hoax from October 15, 2009 led people to believe that a six year old boy had floated away in a home made helium balloon when in fact he was hiding at his house the whole time.
  
• Because helium is less dense than normal air, when inhaled from a source such as a helium balloon it briefly changes the sound of a person’s voice, making it much sound much higher. However, breathing in too much helium can be very dangerous, potentially choking people due to a lack of oxygen.
  

 

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• Helium can be in a liquid and even solid state but they can only occur at temperatures near absolute zero.
  
• Liquid helium is used to cool metals for superconductivity use. The European Organization for Nuclear Research’s (CERN) Large Hadron Collider uses liquid helium to maintain an extremely low temperature.
  

 

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Helium is often used in space programs, displacing fuel in storage tanks and having other rocket fuel applications.

 

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Carbon Facts:

• Carbon is a chemical element with the symbol C and atomic number 6.
  
• The word carbon comes from the Latin word carbo, meaning coal.
  

 

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• Carbon forms a large number of compounds, more than any other element. Because of its willingness to bond to other nonmetallic elements it is often referred to as the building block of life.
  
• While carbon forms many different compounds it is a relatively unreactive element.
  

 

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• There are several allotropes (different forms) of carbon with the three most well known being amorphous carbon (coal, soot etc), diamond and graphite.
  
• The properties of diamond and graphite are very different with diamond being transparent and very hard while graphite is black and soft (soft enough to write on paper).
  

 

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• Graphite is used for its thermal insulation (lower rate of heat transfer) properties. It is also a very good conductor of electricity.
  
  
• The carbon atoms in graphite are bonded in flat hexagonal lattices and layered in sheets.
  

 

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• Carbon is the 4th most common element in the Universe (after hydrogen, helium and oxygen). It is the 15th most common element in the Earth’s crust while it is the second most common element in the human body (behind oxygen).
  
• Carbon has the highest melting point of all elements, around 3500 °C (3773 K, 6332 °F).
  

 

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• Hydrocarbons are organic compounds made entirely of molecules featuring just hydrogen and carbon. Organic chemistry involves the study of hydrocarbons.
  
• The simplest hydrocarbon compound is methane (CH[SUB]4[/SUB]).
  

 

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• Carbon was discovered by early human civilizations in the form charcoal and soot.
  
• The term carbon footprint refers to the amount of greenhouse gas emissions caused by a country, organization or individual person.
  

 

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• The carbon cycle is the process in which carbon is exchanged between all parts of Earth and its living organisms. It is of vital importance to life on Earth, allowing carbon to be continually reused and recycled.
  
• Carbon is found in the Earth’s atmosphere in the form of carbon dioxide (CO[SUB]2[/SUB]). Although it only makes up a small percentage of the atmosphere it plays an important role, including being used by plants during photosynthesis.
  

 

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• Carbon monoxide (CO) is very toxic to both humans and animals. It forms in conditions when there is not enough oxygen to form carbon dioxide (CO[SUB]2[/SUB]). In many countries around the world, carbon monoxide poisoning is the most common kind of fatal poisoning.
  
• Carbon fiber is a strong material that consists of thin fibers made up largely of carbon atoms which are bonded together in microscopic crystals. It is very useful for applications needing high strength and low eight.