From the above discussion, it can be concluded that chelating ligand EDTA is a process of reversible bond formation of a ligand that serves as chelating ( chelting agent or Chelator) that exist within the compound of EDTA. Basically, EDTA combines with some specific ion, so it causes the functions of EDTA as chelator. When the functions of EDTA as chelator, EDTA is a liquid ( solution)
2.3 Volcanic Ash Volcanic ash or sand is volcanic material debris that spouted into the air during an eruption. Sand or Volcanic ash consists of a large stone until a smooth stone. The large stone usually falls around the radius of up to 5 - 7 km from the crater, while the smooth stone can fall up to hundred kilometres …show more content…
Corrosion is called rust. The example of common corrosion are corrosion of metal and iron. Corrosion on metal occurs due to the interaction between metal and the environment that is corrosive, i.e. humid environments(containing water vapor) and induced by the presence of O2, CO2, or H2S. Corrosion can also occur due to high temperature. Corrosion on metals can also be viewed as the process returns to its original state of metal, namely metal ores. For example, corrosion on the iron becomes iron oxide or iron …show more content…
The color on rust are varied, ranging from yellow to red-brown and even black. These color depends on the amount of H2O molecules bound to rust. Gold with the standard reduction potential 1.5 V is greater than the standard reduction potential gas O2 (1.23 V) so that gold does not corrode in the open air. In nature there is as pure metal gold.
2.4.3 The Factors Affecting Corrosion Corrosion can occur if there are air (especially gas O2) and water. If there is only water or gas O2 only, the corrosion will not occur. The presence of salt dissolved in the water will accelerate the process of corrosion. This is due to the salt in the solution there is ions which can help accelerate the ions Fe2 + oxidation results. Violence of rust increased quickly by the presence of salt because the salt solubility increase conductivity ions by the solution so that it speeds up the process of corrosion. Ions chloride also forms a stable complex with compounds Fe3 +. These factors tend to increase the solubility of iron so that it can accelerate