Ionic compound double displacement reactions

In Chapter 9, as in most of Unit 4, you learned about equilibrium reactions. In this section, you analyzed precipitation reactions. You mainly examined double-displacement reactions—reactions in which two soluble ionic compounds react to form a precipitate. You used the solubility product constant, Ksp, to predict whether or not a precipitate would form for given concentrations of ions. In Unit 5, you will learn about a class of reactions that will probably be new to you. You will see how these reactions interconvert chemical and electrical energy. 

Many double displacement reactions occur between ionic compounds that are dissolved in water. Sometimes one of the products of a double displacement reaction will come out of solution, usually as a gas or a precipitate. Solutions are mixtures of two or more substances, called the solutes, dissolved in another substance, the solvent. For example, salt water is a solution. The salt is the solute and the water is the solvent. In a solution, it is impossible to see the separate parts. But if two chemicals that are dissolved in water... 

A double displacement reaction involves the exchange of cations between two ionic compounds, usually in aqueous (water) solution. A double displacement reaction is also known as a double replacement reaction. 

Double displacement reactions tend to occur in aqueous solution. Not all ionic compounds, however, will react with one another in this way. You can tell that a double displacement reaction has taken place in the... 

What happens if both products are soluble ionic compounds Both ionic compounds will be ions dissolved in the water. If neither product precipitates out, no reaction occurs. Try the following problem to practise writing the products of double displacement reactions and predicting their states. 

Neutralization reactions are a special type of double displacement reaction that produces water. Neutralization involves the reaction of an acid with a base to form water and an ionic compound. You will learn more about neutralization reactions in Chapter 10. For example, the neutralization of hydrogen nitrate (nitric acid) with sodium hydroxide (a base) is a double displacement reaction. 

When you mix two aqueous ionic compounds together, there are two possible outcomes. Either the compounds will remain in solution without reacting, or one aqueous ionic compound will chemically react with the other. How can you predict which outcome will occur Figure 9.4 shows what happens when an aqueous solution of lead(II) nitrate is added to an aqueous solution of potassium iodide. As you can see, a yellow solid—a precipitate—is forming. This is a double displacement reaction. Recall, from Chapter 4, that a double displacement reaction is a chemical reaction that involves the exchange of ions to form two new compounds. It has the general equation... 

The reaction of two compounds may yield two new compounds. Many reactions that occur in aqueous solution involve two ionic compounds trading anions. This class of reactions is called double substitution reactions, double displacement reactions, or metathesis reactions. As usual, the correct formulas must be written for the products before the equation is balanced. In a double substitution reaction, if the ions are not converted to covalent compounds, their charges do not change as they are converted from reactants to products. 

In double-displacement reactions, the positive portions of two ionic compounds are interchanged. For a double-displacement reaction to take place, at least one of the products must be a precipitate or water. An example of a double-displacement reaction is shown in Figure 6.11. 

In order to predict whether a precipitation reaction will take place when two aqueous ionic compounds are mixed, you need to be able to predict whether the possible products of the double-displacement reaction are soluble or insoluble in water. 

Neutralization reactions between strong monoprotic acids, such as Q aq), and ionic compounds, such as KOH, are double-displacement reactions, so they have the form AB + CD AD + CB... 

Double displacement (metathesis) reactions. This reaction commonly occurs in solution when the reactants produce ionic solution with an exchange of ions if one combination produces a compound that precipitates an insoluble salt. 

DNA deoxyribonucleic acid. (Chap. 19, p. 688) double bond a bond formed by the sharing of two pairs of electrons between two atoms. (Chap. 9, p. 321) double displacement a type of reaction where the positive and negative portions of two ionic compounds are interchanged at least one product must be water or a precipitate. (Chap. 6, p. 208) ductile property of a metal that means it can easily be drawn into a wire. (Chap. 9, p. 313) dynamic equilibrium term describing a system in which opposite reactions are taking place at the same rate. (Chap. 6, p. 211)... 

In this reaction, which is a double-displacement type, the from the acid combines with the OH from the base to form water. The ionic compound must be composed of the other two ions, and Br . We determine the formula of the ionic compound to be KBr from the fact that K is a -l-l cation and Br is a -1 anion. The final balanced equation is... 

Na2S04. Then classify these substances as acids, bases, or ionic compounds. Both substances are ionic compounds. Since both substances are compounds, the reaction will be of the double-displacement type. Start writing the equation with the reactants ... 

The carbon-metal bond in such compounds can range from an almost completely ionic bond to one that is predominantly covalent. Benzyl-sodium, for example, may be dissolved in ether to yield a conducting solution on the other hand, the lithium-carbon bond in the colorless ethyliithium is quite nonpolar. The chemistry of such compounds, be they ionic or covalent, is best understood by considering them as sources of the highly basic carbanions that would be formed by removal of the metal ion thus the chemistry of benzylsodium is the chemistry of the CeH CH ion, whereas the chemistry of ethyliithium is the chemistry of the ethide ion, C2H Such ions will attack acidic hydrogens to form the parent hydrocarbons, will attack the more positive end of a double bond, and can carry out a number of nucleophilic displacements these reactions are discussed in texts on organic chemistry. 

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