Nursing Preparation Study Guide

Nursing Preparation Study Guide isolation or combination. The interactions, reactions, and transformations that are studied in chemistry are a result of interactions either between different chemical substances or between matter and energy. A chemical reaction is a transformation of some substances into one or more different substances. A chemical equation is a method for symbolically depicting a chemical reaction. Oftentimes, in a chemical transformation equation, the number of atoms on the left and the right are equal. The nature of chemical reactions a substance undergoes and the accompanying energy changes are constrained by certain basic rules, also called chemical laws. In nearly all chemical studies, energy and entropy considerations are undoubtedly important. In addition to being classified based on structure and phase, chemical substances are also categorized according to their chemical compositions. They can be analyzed using the tools of chemical analyses – spectroscopy and chromatography. Compound A compound is a substance with a particular ratio of atoms of certain chemical elements that determine its composition with a particular organization that determines its chemical properties. For instance, water is a compound that contains the elements hydrogen and oxygen in a 2:1 ratio, with the oxygen atom between the two hydrogen atoms, and an angle of 104.5° between them. Chemical reactions are responsible for forming and interconverting compounds. Substance A chemical substance is matter with a definite set of properties and composition. In other words, a mixture of elements, compounds, or a combination thereof is not a chemical substance, but it may be called a chemical. Most of the substances we encounter in our daily life are some kind of mixture, such as air, alloys, biomass, etc. Nomenclature, or the system used for naming chemical compounds, is a major part of the language of chemistry. Earlier in the history of chemistry, substances were given names by their discoverer, which often led to some confusion and difficulty. Today, the IUPAC system of chemical nomenclature allows chemists to identify by name specific compounds amongst the vast variety of possible chemicals. The International Union of Pure and Applied Chemistry (IUPAC) sets the standard nomenclature of chemical substances. Organic compounds are termed based on the organic nomenclature system, while inorganic compounds are named according to the inorganic nomenclature system. Additionally, the Chemical Abstracts Service has devised a method to index chemical substance. In this scheme, each chemical substance is identifiable by a number known as the CAS registry number.

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