Nursing Preparation Study Guide

Nursing Preparation Study Guide Evaporation depends on three main factors, which are atmospheric pressure as determined by the humidity percentage, heat, and air movement. Therefore, evaporation increases as temperature or wind conditions increase. It is also important to note that as the molecules escape with the heat and energy, the remaining water has reduced kinetic energy and temperature. Water temperature declines as evaporation occurs, also known as evaporation cooling. Vaporization Vaporization is a process in which a liquid is converted into a gas. Vaporization happens either by evaporation or boiling. Sublimation occurs when the transition from the liquid phase to the solid phase occurs without the gas phase. The word “vaporization” has also been used to describe the extensive destruction of physical objects exposed to intense heat, or the effect of nuclear weapons. For example, the bodies in Nagasaki and Hiroshima are described as having been vaporized after the 1945 atomic bombings. Condensation Condensation is the transition from a gaseous phase to a liquid phase. Condensation is the reverse of vaporization. If the transition is from a gas to a solid phase, without going through a liquid phase, it is called deposition. Condensation occurs when the temperature of the gas molecules drops or the molecules within the gas combine to form clusters. Condensation can also occur when gas molecules come in contact with a solid or liquid surface. Oxidation and Reduction Oxidation is a chemical reaction involving the loss of electrons or the increase of the oxidation state of an element by an atom, molecule, or ion. Reduction is the opposite side of the chemical reaction that involves the gain of an electron, or the decrease in the oxidation state of an element by an ion, molecule, or atom. Originally, the word oxidation was used to refer only to the reaction of an element with oxygen to produce an oxide. Oxygen was the first recognized oxidizing agent, thus the name “oxidation”. The use of the word oxidation later expanded to include reactions with any element or substances that accomplish parallel chemical reactions as that produced by oxygen. Today, oxidation refers to all processes and reactions that involve a loss of electrons or an increase in the oxidation state. The word “reduction” was originally used to refer to all chemical reactions that involved the loss of weight of a metallic ore or metal oxide by heating. When a metal oxide is heated to extract the metal, oxygen is lost as a gas and the overall weight decreases. In time, it was discovered that the metallic ore or element being reduced actually gained some electrons. Today, the chemical application of the

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