Chemical reaction double displacement

When acids and bases come into contact with one another, a chemical reaction called a neutralization reaction takes place. A neutralization reaction is a double displacement reaction. In a double displacement reaction, the positive ions from one reactant take the place of the positive ions in the other reactant. For example, if hydrochloric acid and sodium hydroxide react with one another, the positive sodium ion in sodium hydroxide will take the place of the hydrogen ion in the hydrochloric acid ... 

The subscript after potassium in the chemical formula for potassium sulfate shows that two potassium ions are needed. Potassium sulfate is a salt. When the two equations are put together (as they would occur when the acid and base are mixed together), they represent the double displacement neutralization reaction that occurs between sulfuric acid and potassium hydroxide ... 

Double displacement reaction A chemical reaction in which the positive ion in one reactant takes the place of the positive ion in the other reactant. 

For either of the ternary complex mechanisms described above, titration of one substrate at several fixed concentrations of the second substrate yields a pattern of intersecting lines when presented as a double reciprocal plot. Hence, without knowing the mechanism from prior studies, one can not distinguish between the two ternary complex mechanisms presented here on the basis of substrate titrations alone. In contrast, the data for a double-displacement reaction yields a series of parallel lines in the double reciprocal plot (Figure 2.15). Hence it is often easy to distinguish a double-displacement mechanism from a ternary complex mechanism in this way. Also it is often possible to run the first half of the reaction in the absence of the second substrate. Formation of the first product is then evidence in favor of a doubledisplacement mechanism (however, some caution must be exercised here, because other mechanistic explanations for such data can be invoked see Segel, 1975, for more information). For some double-displacement mechanisms the intermediate E-X complex is sufficiently stable to be isolated and identified by chemical and/or mass spectroscopic methods. In these favorable cases the identification of such a covalent E-X intermediate is verification of the reaction mechanism. 

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. 

Metathesis. A chemical reaction involving a double displacement. That is, groups from two different compounds play musical chairs and form two new compounds when the music stops. 

The purines and pyrimidines are relatively stable compounds with considerable aromatic character. Nevertheless, they react with many different reagents and, under some relatively mild conditions, can be completely degraded to smaller molecules. The chemistry of these reactions is complex and is made more so by the fact that a reaction at one site on the ring may enhance the reactivity at other sites. The reactions of nucleic acids are largely the same as those of the individual nucleosides or nucleotides, the rates of reaction are often influenced by the position in the polynucleotide chain and by whether the nucleic acid is single or double stranded. The reactions of nucleosides and nucleotides are best understood in terms of the electronic properties of the various positions in the bases.26 33 Most of the chemical reactions are nucleophilic addition or displacement reactions of types that are discussed in Chapters 12 and 13. 

In bi-substrate reactions of the double displacement type, one substrate must be bound and one product released before the entry of the second substrate. In such reactions, the first substrate reacts with the enzyme to yield a chemically modified form of the enzyme (usually a functional group is changed) and the first product. In the second step, the functional group of the modified enzyme is transferred from the enzyme to the second substrate to form the second product. A good example is the aminotransferase class of enzymes, where an amino group is transferred from an amino-acid to the enzyme, from which it is transfered to a keto-acid. 

Fe is the chemical symbol for iron. It comes from iron s Latin name, Ferrum. In this reaction, the iron in iron oxide (Fe2Os) switches places with the hydrogen in the hydrochloric acid (HCl). Double displacement reactions are like two pairs of dancers switching partners. 

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... 

In the double displacement reaction above, dissolved sodium cyanide (NaCN) and sulfuric acid (H2S04) react to form sodium sulfate (Na2S04) and an extremely poisonous gas called hydrogen cyanide (HCN). The (aq) means these substances are an aqueous solution. An aqueous solution is made by dissolving chemicals in water. In this reaction, the sodium cyanide, sulfuric acid, and sodium sulfate are all dissolved in water. The (g) that follows the formula for hydrogen cyanide indicates that this chemical is a gas. The hydrogen cyanide will bubble out of the solution, leaving behind the sodium sulfate that is still dissolved in the water. 

A precipitate is a solid that separates from a solution as the result of a chemical reaction. You will learn more about precipitates in Chapter 9. Many double displacement reactions involve the formation of a precipitate. 

In summary, to determine the products and their physical states in a double displacement reaction, you must first deconstruct the reactants. Then switch the cations, and reconstruct the products using proper chemical formulas. You should then balance the chemical equation. You will be given information to determine which of the products, if any, will form a precipitate. Finally, you can write the physical state—(s) or (aq)— of each product and balance the equation. 

Write a balanced chemical equation for each double displacement reaction. Write NR if you predict that no reaction will occur. Note that K+, Na+, and Li+ ions form soluble compounds with all anions. All nitrate compounds are soluble. Sulfate compounds with Ca2+,... 

Consider the reaction of aqueous sodium carbonate (washing soda) and hydrochloric acid, shown in Figure 4.17. Hydrochloric acid is sold at the hardware store under the common name muriatic acid. If you carry out this reaction, you immediately see the formation of carbon dioxide gas. The first reaction that takes place is a double displacement reaction. Determine the products in the following way. Separate the reactions into ions, and switch the anions. Write chemical formulas for the products and balance the equation. 

Another double displacement reaction results in the formation of gaseous ammonia, NH3. Ammonia, a pungent-smelling gas, is an important industrial chemical. It is used as a fertilizer and, when dissolved in water, as a household cleaner. Ammonium hydroxide is formed in the reaction below... 

For each reaction in Table B, write the appropriate balanced chemical equation for the double displacement reaction. Then write a balanced chemical equation for the decomposition reaction that leads to the formation of a gas and water. 

In sections 4.2 and 4.3, you have examined five different types of chemical reactions synthesis, decomposition, combustion, single displacement, and double displacement. Equipped with this knowledge, you can examine a set of reactants and predict what type of reaction will occur and what products will be formed. The Concept Organizer above provides a summary of the types of chemical reactions. 

Classify each reaction as synthesis, decomposition, single displacement, double displacement, or combustion. Also, balance each chemical equation. 

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... 

In this section, you will examine each of these results. At the same time, you will learn how to represent a double displacement reaction using a special kind of chemical equation an ionic equation. 

Suppose that you have a sample of water. You want to know what, if any, ions are dissolved in it. Today technological devices, such as the mass spectrometer, make this investigative work fairly simple. Before such devices, however, chemists relied on wet chemical techniques experimental tests, such as submitting a sample to a series of double displacement reactions. Chemists still use wet chemical techniques. 

Write balanced chemical equations and net ionic equations for double-displacement reactions. 

Two pairs of chemically matched reactions exemplify the importance of shared binding sites in the evolution of double-displacement pathways. They are the reactions catalyzed by UDP-glucose pyrophosphorylase (inversion) [74] and galactose- -P uridylyltransferase (retention) [21], which catalyze Reactions 21 and 22,... 

At the classificatory or theoretical level, various affinities corresponded to different categories of chemical actions or combinations. Elective affinity referred to the displacement reaction of a salt by an acid complex affinity referred to the double displacement reactions of two... 

Identify double-displacement reactions, and write chemical equations that predict the products. 

Let s suppose we were to carry out a chemical reaction between aqueous solutions of lead (II) chlorate and sodium iodide. We mix the two solutions in a test tube, and we find that a solid precipitate forms and falls to the bottom of the test tube. We would want to be able to identify what the solid was. The first thing that we might want to do is make a word equation for the reaction that we think is taking place. Treating this as a double displacement reaction, we would get the word equation shown here ... 

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