Carbon Dioxide off the Air

Good news. Researchers at Newcastle University are working on a new technology that is responsible for converting the greenhouse gas carbon dioxide into cyclic carbons. This is achieved by reacting carbon dioxide with epoxides. However, this reaction requires enormous energy or harsh conditions. Therefore, a catalyst is required and the type of catalyst has been figured out. Aside from the reaction reducing the global warming causing gas, carbon dioxide, the reaction produces cyclic carbons which are commercially in demand. These cyclic compounds are used to create solvents, paint-strippers, biodegradable packaging and other applications. If successful, this technology will decrease England's carbon dioxide output by 18 tons of CO2 or more per year.
For more info, refer to the following site:

http://www.sciencedaily.com/releases/2008/04/080424103217.htm

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Energy of the Sun

It’s a remarkable feature of the sun to have so much energy that has an effect here on earth from millions of miles away. But where does this energy come from? That energy comes from the suns core where an important reaction occurs. In the suns core, the pressure is very high and therefore gives hydrogen gas molecules to move in a small volume. This leaves the hydrogen atoms no choice but to bump into each other. Once they do, they form a heavier nucleus, helium. This process is called nuclear fusion where small atoms fuse together to form heavier nucleus. During that process, some mass is lost in forming the helium atom but through Einstein’s famous equation: E=mc², that mass is converted to energy. That energy is then sent to earth. Unfortunately, during the fusion process, radiation such as gamma rays is also created and it also travels with the energy to reach earth. Therefore it is wise to use sun tan lotion when in the beach.

Crude Crude Crude

So you discovered that your house is sitting on a land that contains crude oil. You know you are going to be rich because crude oil consists of a mixture of hydrocarbon components that are essential in today’s industry. But, do you know how to separate those hydrocarbons from that mixture of crude oil? If you are aware of fractional distillation, then you have nothing to worry about but if you are not aware of it, then read up.

First of all, the crude oil is found in its liquid form. What we want to do is convert it to the gaseous form. So crude oil is subjected to a curved pipe (furnace) where it is heated and converted to a gas. Then that gas, which is a mixture of the hydrocarbons that made up the crude oil, enters a tower. In this tower, the physical properties of hydrocarbons are taken advantage off. The bottom of the tank is warm and as we move up the tower, its gets cooler. We all know that gas tends to condense at cooler temperatures. So as this gas mixture from the crude oil moves up the tower, the hydrocarbons condense back to liquid at their corresponding boiling points. The hydrocarbons that have high boiling points condense at the bottom of the tower (warm) and those that have low boiling points condense at cooler temperatures (cooler). This whole process is called fractional distillation. You have just separated crude oil into its major components. So now you know what is happening in those large industrial pipes that release gas into the atmosphere.

Synthetic Diamonds

It was a very exciting time when scientist found out that diamonds are nothing more than an allotrope of carbon. In other words, it was made from only carbon atoms that also happen to make up its cousin graphite. But why is diamond "hard" and has the ability to scratch any surface while its cousin graphite is "soft" and is a lubricant. The answer to that question has to do with molecular structure of the two species. The graphites molecular structure consists of sheets of carbon atoms covalently linked with other sheets of carbons. This allows the sheets of carbon atoms to slip over each other. Hence graphite is a lubricant at STP conditions. In contrast, the carbons atoms of diamond orient themselves in a tetrahedral manner forming a tetrahedral network. This network is very strong and stable and that what makes diamonds very hard. This was all interesting to scientists but what they wanted to know was: since both diamond and graphite consist of carbon atoms, is there any way to convert the cheap graphite to its valuable form diamond?




This requires the understanding of thermodynamics. Thermodynamics dictates that in order to convert graphite to diamond, a negative ΔG is required for it to happen spontaneously. Of course, the more negative ΔG is, the faster the rate. But at what conditions is this ΔG negative? Certainly not in atmospheric conditions where the pressure is 1 atm and temperature is 293 K. That is why diamonds are never formed on the Earths crust but below it where the conditions are much more harsh. These conditions supply the sufficient energy for the formation of diamonds. Therefore it requires extreme conditions to accomplish this conversion and 1950s, technology was created that could withstand those conditions and complete the conversion at a reasonable rate. The conditions of that conversion were pressure in excess of 100,000 atm and temperature about 2800 Celsius. When graphite is subjected to these conditions, the carbon atoms of graphite rearrange themselves in a tetrahedral network and diamonds are formed. The synthetic diamonds that are formed are very small and could not be formed into a gem, but they were sufficient enough for industrial use such as coating and cutting. For more extensive details, visit the following links.

• http://www.bristol.ac.uk/Depts/Chemistry/MOTM/diamond/diamond.htm


• http://www.chem.wisc.edu/~newtrad/CurrRef/BDGTopic/BDGtext/BDGDmnd.html