Polar covalent compound

Many of the reactions that you will study occur in aqueous solution. Water is called the universal solvent, because it dissolves so many substances. It readily dissolves ionic compounds as well as polar covalent compounds, because of its polar nature. Ionic compounds that dissolve in water (dissociate) form electrolyte solutions, which conduct electrical current owing to the presence of ions. The ions can attract the polar water molecules and form a bound layer of water molecules around themselves. This process is called solvation. Refer to the Solutions and Periodicity chapter for an in-depth discussion of solvation. 

Classify the honding in each of the following as covalent (non-polar), polar covalent, or ionic. Afterwards, rank the polar covalent compounds in order of increasing polarity. 

Solubility data are presented for practically all entries. Quantitative data are also given for some compounds at different temperatures. In general, ionic substances are soluble in water and other polar solvents while the non-polar, covalent compounds are more soluble in the non-polar solvents. In sparingly soluble, slightly soluble or practically insoluble salts, degree of solubility in water and occurrence of any precipitation process may be determined from the solubility product, Ksp, of the salt. The smaller the Ksp value, the less its solubility in water. 

You have seen how Lewis structures can help you draw models of ionic, covalent, and polar covalent compounds. When you draw a Lewis structure, you can count how many electrons are needed by each atom to achieve a stable octet. Thus, you can find out the ratio in which the atoms combine. Once you know the ratio of the atoms, you can write the chemical formula of the compound. Drawing Lewis structures can become overwhelming, however, when you are dealing with large molecules. Is there a faster and easier method for writing chemical formulas ... 

Hydration is usually highly exothermic for ionic or polar covalent compounds, because the polar water molecules interact very strongly with ions and polar molecules. In fact, the only solutes that are appreciably soluble in water either undergo dissociation or ionization or are able to form hydrogen bonds with water. 

The relationship between submicroscopic structure and macroscopic properties is an important part of the study of chemistry. Use an ionic compound, a nonpolar covalent compound, and a polar covalent compound to illustrate this relationship. (Chapter 1)... 

The role of water in the solution process deserves special attention. It is often referred to as the "universal solvent" because of the large number of ionic and polar covalent compounds that are at least partially soluble in water. It is the principal biological solvent. These characteristics are a direct consequence of the molecular geometry and structure of water and its ability to undergo hydrogen bonding. 

Polar covalent compounds, such as HCl, dissociate in water and, thus, are electrolytes. Carboxylic acids, the family of organic compounds we will study in Chapter 15, are weak electrolytes when dissolved in water. 

Figure 13-5 shows that polar covalent compounds with hydrogen bonding (H2O, HF, NH3) boil at higher temperatures than analogous polar compounds without hydrogen bonding (H2S, HCl, PH3). Symmetrical, nonpolar compounds (CH, SiH ) of compa-... 

Polar covalent compounds (e.g., alcohols Nonpolar covalent compounds (e.g.. 

Another unique property of water is its ability to dissolve a large variety of chemical substances. It dissolves salts and other ionic compounds, as well as polar covalent compounds such as alcohols and organic acids. In fact, water is sometimes called the universal solvent because it can dissolve so many things. It can also absorb a large amount of heat, which allows large bodies of water to help moderate the temperature on earth. 

Determine whether each of the following atoms will form a nonpolar covalent compound or a polar covalent compound, and give the formula of the compound. 

Many of the reactions of interest in the course you are taking occur between compounds or elements dissolved in water. Ionic compounds and some polar covalent compounds break apart (dissociate) into ions when they are dissolved in water. Thus, a water solution of sodium hydroxide (NaOH), an ionic compound, does not contain molecules of NaOH but, rather, contains equal numbers of sodium ions (Na ) and hydroxide ions (OH ). Covalently bonded hydrogen chloride, HCl, dissolves readily in water to form and Cr ions. Equations for reactions between substances that form ions in solution can be written in several ways. For example. Equation 5.22 contains three substances that form ions, HCl, NaOH, and NaCl. Equation 5.22 is written in the form of a molecular equation in which each compound is represented by its formula. This same reaction, when represented by a total ionic equation, becomes... 

FIGURE 10.4 An illustration of a strong acid dissolving in water. The acid is a polar covalent compound, like sugar, but when it dissolves in water, it ionizes—that is, the hydrogen atoms break away from the molecule, forming hydrogen ions (+ ions) and - ions. It is a total, complete ionization. 

Polar covalent compounds, such as acids. Examples hydrochloric acid, sulfuric acid, sugar. 

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