Drainless Steel Research Paper

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Stainless steel is a product that we see in everyday life, from kitchen appliances to medical tools to constructions materials. But what is the substance that gives it this wondrous stainless characteristic? It is Chromium!
Chromium is a transition metal in period number 4 and group number 6 under the symbol Cr and atomic number 24 on the periodic table. It has an atomic weight of 51.9961 rounding to 52, melting point of 2180K and boiling point of 2944K. It was discovered by Louis-Nicholas Vauquelin in 1797.
Stainless steel is a compound that commonly contains iron, chromium, manganese, silicon, carbon, nickel and molybdenum. These alloying elements within stainless steel keeps it from rusting by interacting with each other and the environment. …show more content…

The expected electron configuration using Aufbau law is 1s2 2s2 2p6 3s2 3p6 3d4 4s2, which simplify to [Ar] 3d4 4s2; electrons are filling up each orbital in order. However, there are some exceptions in this law, this occur to what are called the anomalous elements that include chromium, its factual electron configuration is [Ar] 4s1 3d5. This is because half-filled orbitals are more stable than partially filled orbitals, therefore, one of the electrons in the 4s orbital is transferred into the 3d orbitals to make it half-filled. This gives it the stability before it bonds with other elements and this also gives it several oxidation states as it has a half-filled …show more content…

In both of these molecules, chromium and iron both form 3+ ions which means their ionic size is changed from atomic size in similar ways. However, because iron is further to the right of the periodic table, its ionic size is smaller than that of chromium. This is because the number of protons in iron is greater than chromium but they are pulling electrons from the same outer shell resulting in the electrons being pulled more closely to the nucleus, this means that the ion of iron will be smaller than ion of chromium. This causes the problem for iron when forming oxides, iron ion being too small compared to its oxide results in the bonding becoming loose. When oxides bond around the iron ion, it attracts closely to the iron because they have opposite charge, a strong 6+ to 6- attraction similar to those of chromium oxide. However, when they are pulled in so close, the oxides will then start coming in to contact and that introduces repulsion because the oxides that have the same charge. This explains the flaking off and rusting in iron oxide metals. On the other hand, chromium does not have this problem because chromium ion is not too small compared to its oxide, added to that is that chromium oxide also have 6+ to 6- attraction though does not have any repulsion between the same ions giving it an extremely strong and

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