Ionic compounds covalent compound

Ionic Compounds Covalent Compounds A Human Perspective ... 

Dinitrogen tetroxide is a poor solvent for ionic compounds. Covalent compounds are frequently soluble as are donor compounds which can react with the solvent. 

Many of the reactions of halogens can be considered as either oxidation or displacement reactions the redox potentials (Table 11.2) give a clear indication of their relative oxidising power in aqueous solution. Fluorine, chlorine and bromine have the ability to displace hydrogen from hydrocarbons, but in addition each halogen is able to displace other elements which are less electronegative than itself. Thus fluorine can displace all the other halogens from both ionic and covalent compounds, for example... 

In its chemistry, cadmium exhibits exclusively the oxidation state + 2 in both ionic and covalent compounds. The hydroxide is soluble in acids to give cadmium(II) salts, and slightly soluble in concentrated alkali where hydroxocadmiates are probably formed it is therefore slightly amphoteric. It is also soluble in ammonia to give ammines, for example Of the halides, cadmium-... 

Apart from the three broad categories of student conceptions discussed above, students displayed several inappropriate conceptions relating to the stractural properties of substances. For example, 14% of students suggested that Mg + ions were present in magnesium ribbon. A second example involved the chemical reaction between copper(II) oxide powder and dilute sulphuric acid. In this instance, 25% of students suggested that Cu + ions were present only in aqueous solution but not in the solid and liquid states. This view was rather unexpected because students had earlier been introdnced to ionic and covalent compounds. It is likely that students had merely rote-learned the general rale without sufficient understanding that ionic solids are formed between metallic and non-metallic elements. 

The insoluble compound is written as one compound even though it is ionic. The covalent compound is written together because it is not ionic. 

In this section, you have used Lewis structures to represent bonding in ionic and covalent compounds, and have applied the quantum mechanical theory of the atom to enhance your understanding of bonding. All chemical bonds—whether their predominant character is ionic, covalent, or between the two—result from the atomic structure and properties of the bonding atoms. In the next section, you will learn how the positions of atoms in a compound, and the arrangement of the bonding and lone pairs of electrons, produce molecules with characteristic shapes. These shapes, and the forces that arise from them, are intimately linked to the physical properties of substances, as you will see in the final section of the chapter. 

Greater ratios up to H M = 4.5, for example in BaReHg, have been found [43] however, all hydrides with a hydrogen to metal ratio of more than 2 are ionic or covalent compounds and belong to the complex hydrides. 

Acids react with HgO to produce corresponding Hg(II) compounds. Two classes of Hg(II) compounds maybe defined covalent and ionic. The covalent compounds HgCl2, HgBr2, HgD, and Hg(CN)2 go into HOH solution chiefly as undissociated molecules, which undergo little hydrolysis. The ionic compounds which include HgF2, Hg(N03)2, HgS04, and Hg(C104)2 go into... 

The azide ion has an ionic radius of 148 pm and forms many ionic and covalent compounds that are similar to those of the halides, (a) Write the Lewis formula for the azide ion and predict the N—N—N bond angle, (b) On the basis of its ionic radius, where in Group 17 would you place the azide ion ... 

Intermetallic compounds can be "valence compounds, with structures corresponding to those of NaCl, CaF2, etc., or compounds of various compositions with all atoms in close-packed layers. Because of the deficiencies of electrons and delocalized bonding, metals are not limited by the valence rules for ionic and covalent compounds. Some intermetallic compounds have structures found only for metals (Chapter 9). 

P. M. F. J. Costa, J. Sloan and M. L. H. Green, Structural studies on single- and double-walled carbon nanotubes filled with ionic and covalent compounds. Ciencia e Tecnologia dos Materials 18, no. 3-4, 78-82 (2006). 

This section has demonstrated the strikingly unique nature of fluorine, both as an atom and in ionic and covalent compounds. With this in mind, we move on to a discussion of electronegativity equalization and its impact upon molecular properties. 

The nomenclature for molecular compounds is much less complicated than for ionic compounds. Molecular compounds are formed from covalently bonded nonmetallic elements. The formula for a molecule represents a stable unit of atoms, unlike a formula for an ionic compound, which only represents the simplest whole number ratio of ions. As a result, molecular formulas cannot be simplified like formulas for ionic compounds. An example would... 

The different properties of ionic and covalent compounds result from the manner in which chemical bonds form between atoms in these compounds. Atoms can either exchange or share electrons. 

In this section, you learned that most elements do not exist in their pure form in nature. Rather, they exist as different compounds. You reviewed the characteristic properties of ionic and covalent compounds. You considered the periodic nature of electronegativity, and you learned how to use the electronegativity difference to predict the type of bond. You learned, for example, that ionic bonds form between two atoms with very different electronegativities. 

You can use valences to write chemical formulas. This method is faster than using Lewis structures to determine chemical formulas. As well, you can use this method for both ionic and covalent compounds. In order to write a chemical formula using valences, you need to know which elements (or polyatomic ions) are in the compound, and their valences. You also need to know how to use the zero sum rule For neutral chemical formulas containing ions, the sum of positive valences plus negative valences of the atoms in a compound must equal zero. 

In section 3.4, you learned how to name ionic and covalent compounds. You also learned how to write their formulas. In Chapter 4, you will learn how compounds and elements interact in nature, in the laboratory, and in everyday life. These interactions are responsible for the tremendous variety of substances and materials found on Earth. 

Lewis structures can represent the formation of ionic and covalent compounds according to the octet rule. 

The ability to name compounds and determine the chemical formula for a compound comes from the ability to distinguish between ionic and covalent compounds. The name of a compound depends heavily on the type of bond present between the atoms. Besides being able to identify certain types of bonds, when learning to name compounds it is best to remember the rules that apply to the type of bond in question. The rules for naming four common kinds of compounds are outlined below. 

Be able to name ionic and covalent compounds using both traditional methods and the stock method. 

Ans. We treat the oxidation states in part b just like the charges in part a. In this manner, we can predict formulas for ionic and covalent compounds, (a) X2 Y (b) W2Z. 

We will begin with the systems for naming inorganic binary compounds— compounds composed of two elements—which we classify into various types for easier recognition. We will consider both ionic and covalent compounds. 

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