Nursing Preparation Study Guide

Nursing Preparation Study Guide of 173 higher the gas’s pressure, which is the force exerted on the container’s surface by the molecules. An interesting fact about expansion and compression is that it will always be homogeneous, meaning that as a gas expands to fill a container, there will never be pockets of higher density of molecules in some areas with a lower density of molecules in others. Themolecules will expand to fill the container equally. Plasma Plasma is the next step up from a gas; it is when a gas’s molecules become super-heated – to the point at which molecular bonds break down and the atoms begin shedding their electrons. Although plasma is rarely found on Earth, it is the most common state of matter throughout the universe. It is the primary state of matter in stars, for instance. Plasma has some unique characteristics, not the least of which is that it is ionized, or electrically charged. In many ways, plasma acts like a gas. It lacks any definite shape or volume, and will homogeneously fill any container. It can also be manipulated by electromagnetic fields, which alter its shape or contain it. Plasma is a super-heated, magnetically charged gas. Evaporation, Vaporization, and Condensation Evaporation Evaporation is a vaporization process that occurs only on liquid surfaces. It is a process whereby liquid is converted to gas by the application of heat energy. The liquid itself lacks the required heat energy to convert and escape as gas. With the application of heat, the liquid’s temperature rises and the water molecules on the surface turn to vapor, or gas, and evaporate from the liquid’s surface. Evaporation is different from boiling, which is another form of vaporization. Evaporation occurs only on the surface of the liquid, while boiling affects the entire body of liquid. With boiling, the temperature of the entire liquid rises and the liquid is converted to vapor by the heat. Evaporation is also an important part of life and the water cycle. The sun provides the solar energy needed for natural evaporation to take place as water evaporates from lakes, rivers, oceans, and soil moisture. For evaporation to occur, the surface of the liquid has to be exposed for heat to be applied to the surface of the liquid and for the molecules to be able to escape. With natural evaporation, heat from the sun heats the surfaces of water in oceans, rivers, soil, and other water bodies. The heated molecules will collide with each other and transfer some of the energy to each other in different degrees based on how the collision happened. When a molecule near the liquid’s surface acquires enough kinetic energy it would be able to turn to vapor and escape into the air. Water molecules that escape as vapor go up to the air where they form clouds. ©2018 Achieve Test Prep Page 162