Sunday, May 4, 2008
Carbon Dioxide off the Air
For more info, refer to the following site:
http://www.sciencedaily.com/releases/2008/04/080424103217.htm
Sunday, April 27, 2008
ChemoAnim
http://qcpages.qc.cuny.edu/~aabrakhimov100/
Here you will find a huge selection of chemistry animation database.
Sunday, March 23, 2008
Energy of the Sun
Sunday, March 2, 2008
Crude Crude Crude
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.
Sunday, February 17, 2008
Synthetic Diamonds
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