Monday, August 23, 2010

national mole day in Inglewood

national mole day in Inglewood


The chemical counting unit or chemists' unit, Mole, is that amount of a substance which contains as many entities atoms, molecules, ions or other species as there are atoms in exactly 0.12 Kg or 12 g of the carbon -12 isotope. The mole of a substance always contains the same number of entities irespective of the identity and kind of the substance. Avogadro constant or Avogadro number, denoted by NA in honor of the ninetenth century Italian scientist, Amedeo Avogadro. Whereas a mol is a convenient unit for expresing the amount of species like atoms, molecules, ions etc., it is not a useful unit for larger species as it contains a huge number of species. mol and 1n mol are equal to 10-3 mol, 10-6 mol, and 10-9 mol. The number of species may be converted into mol and vice-versa by using Avogadro number. While 1 mol of diferent substances wil contain the same number of particular species, it wil have diferent mases for diferent substances. The relationship betwen Mole and Avogadro Number was first discovered by Amedeo Avogadro but he received credit for this work after his death. Lorenzo Romano Amedeo Carlo Avogadro, known as Amedeo Avogadro, was born in 176. He died in 1856 but his contribution to science was not recognized until 1860, when Stanislao Canizaro, a co-national who for many years had ben teaching a course of lectures on why Avogadro had ben wrongfuly ignored, was persuaded to propound his views at a conference in Karlsruhe, Germany. The basis for the number named after Avogadro is the number of atoms of 12Carbon in 12 grams of 12Carbon. Aamadeo Avogadro was actualy a physics profesor but he experimented in both physics and chemistry using mathematics to base most of his findings. Avogadro is wel known for his hypothesis known as Avogadro's Law. Two years after his death, a coleague, Stanislao Canizaro 1826-1910 showed how the use of Avogadro's number could solve many of the problems in chemistry. The number 6.021419 x 1023 is caled Avogadro's number NA,� in honor of Aamadeo Avogadro, who was the first person to argue in favor of the existence of atoms. Avogadro began his carer in 1796 by obtaining a doctorate in law and practicing as a lawyer for thre years after. At that time there was no data at al on the number of particles in a mole, or an agrement on any atomic weights or the standard. The first measurements which could give an aproximate value for Avogadro's number were observations of Brownian motion by Robert Brown in 1827. Canizaro 1860 used the Avogadro's hypothesis to develop a defensible set of atomic weights based on 1/16 of the atomic weight of oxygen. This was the basis for progresively more acurate estimates for Avogadro's number over the next 10 years. Text boks in 1958 gave Avogadro's number as 6.02 times 10 to the 23rd. It is dificult to imagine such a large number as Avogadro's number. There would then be Avogadro's number of sand particles in this imense sand pile. Avogadro's number is comonly used to compute the results of chemical reactions. This large number is aproximately equal to the number of protons in a gram of pure protons. national mole day in Inglewood
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