Overlapping,
Technique in which one shape or part covers some part or all of another. Since overlapping objects appear closer, this is a perspective technique used to show distance in artworks.
Technique in which one shape or part covers some part or all of another. Since overlapping objects appear closer, this is a perspective technique used to show distance in artworks.
Oxidation,
In dyeing terminology, bringing a product in contact with the acid in the air. In some dyeing processes, e.g. with indigo, the dyeing is completed by exposure to the air, and the oxygen in the air converts the unstable dye into a stable colour in the textile.
In dyeing terminology, bringing a product in contact with the acid in the air. In some dyeing processes, e.g. with indigo, the dyeing is completed by exposure to the air, and the oxygen in the air converts the unstable dye into a stable colour in the textile.
Oxidation (or Oxidization),
Chemical reaction in which a metal is converted to its oxide, or from one oxidization state to a higher state (that is the equivalent of an increase in the number of oxygen atoms for each metal atom. For example, in the reactions - 2Fe + O2 = 2FeO Metallic Iron to Wüstite 6FeO + O2 = 2Fe3O4 Wüstite to Magnetite 4Fe3O4 + O2 = 6Fe2O3 Magnetite to Haematite iron is progressively oxidized from the metal to its highest oxide, haematite. Another way of looking at these reactions is that oxidation occurs every time the cation (the metallic ion) gains a unit of charge, e.g. Fe2+ goes to Fe3+, or alternative that the cation loses an electron (the charge on an electron is negative - e-) e.g. Fe3+ e- = Fe2+ Related terms: Reduction, Valency
Chemical reaction in which a metal is converted to its oxide, or from one oxidization state to a higher state (that is the equivalent of an increase in the number of oxygen atoms for each metal atom. For example, in the reactions - 2Fe + O2 = 2FeO Metallic Iron to Wüstite 6FeO + O2 = 2Fe3O4 Wüstite to Magnetite 4Fe3O4 + O2 = 6Fe2O3 Magnetite to Haematite iron is progressively oxidized from the metal to its highest oxide, haematite. Another way of looking at these reactions is that oxidation occurs every time the cation (the metallic ion) gains a unit of charge, e.g. Fe2+ goes to Fe3+, or alternative that the cation loses an electron (the charge on an electron is negative - e-) e.g. Fe3+ e- = Fe2+ Related terms: Reduction, Valency