Reaction spectator

Ions that appear on both sides of the equation and that do not take part in the reaction (spectator ions) are deleted. 

In this section, you will begin with the reaction questions. Recall, you are given three partial equations. In each question, you are provided the reactants and any conditions of the reaction. You are then to write a balanced equation for the reaction and answer a question about reaction. The directions for this section tell you to assume that all solutions are aqueous unless otherwise indicated. You are also instructed to represent substances in solution as ions if the material is extensively ionized, and you should omit the formulas for any ions or molecules that are unchanged by the reaction (spectators, for instance). It is necessary to balance the equations in this section. Here is a sample problem that illustrates this portion of the test ... 

The answer is D. This is a straightforward definition-type question. The ions that are present in the solution sometimes do not actually participate in the reaction. By writing the complete ionic equation of such a reaction, we can see that the spectator ions on both sides of the equation are in the same state or form. We can cancel them out and get the net equation of the reaction. Spectator ions are not usually depicted in the net ionic equation. 

In the following example, however, the redox equation only lists the ions important to the reaction (spectator ions, or ions not involved in the actual reaction, are not listed). 

In the entrance channel, the value of Bqh.s is close to zero, so there is practically no coupling between the OH stretching vibrations and the reaction path. As a result, there will be practically no energy flow between those degrees of freedom. This might be expected from a weak dependence of ojoh as a function of s. Once more, we see that the OH bond plays only the role of a reaction spectator. 

On the other hand, a chemist always has some additional information on which chemical reactions are expected to occur. Very often the most important changes happen in a limited set of atoms e.g., in functional groups, their reactivity being quite well understood. Freezing the positions of those atoms which are reaction spectators only, allows us to limit the number of degrees of freedom to consider. 

A net ionic equation for a reaction in aqueous solution includes only compounds and ions that change chemically in the reaction. Spectator ions are ions that do not take part in such a reaction. 

Na (a ) and OH (a ) both appear as reactants and products in the ionic equation for the reaction of Na2S04(a ) with Ba(OH)2(a ). Ions that appear on both sides of the equation arrow are called spectator ions because they do not participate in the reaction. Spectator ions cancel one another, just as identical terms on both sides of an algebraic equation cancel one another, so we need not show spectator ions in chemical equations. 

A spectator ion is one that is not involved in the reaction. Spectator ions appear on both sides of the ionic equation. A net ionic equation is an ionic equation from which spectator ions have been eliminated. 

When we omit the ions that do not change during the reaction spectator ions), we obtain the net ionic equation. 

Equations such as this that exclude spectator ions, which take no part in the reaction, are Spectator ions are in solution before,... 

The Na+ and N03 ions take no part in the reaction and so do not appear in the equation. Here again, we are dealing with spectator ions. ... 

Spectator ion An ion that, although present, takes no part in a reaction, 279,82-83, 372-373,399 Spontaneity of reaction concentration and, 465-467,475-476q entropy and, 453-458 free energy and, 458-471 pressure effects, 465-467,475-476q process, 451-453 redox, 489-490... 

FIGURE 1.5 (a) Silver chloride precipitates immediately when sodium chloride solution is added to a solution of silver nitrate, (b) If we imagine the removal of the spectator ions from the complete ionic reaction (top), we can focus on the essential process, the net ionic reaction (bottom). 

Because the Na+ and N03 ions appear as both reactants and products, they play no direct role in the reaction. They are spectator ions, ions that are present while the reaction takes place but remain unchanged, like spectators at a sports event. Because spectator ions remain unchanged, we can simplify the chemical equation by canceling them on each side of the arrow in the ionic equation ... 

Canceling the spectator ions leaves the net ionic equation for the reaction, the chemical equation that displays the net change taking place in the reaction ... 

A complete ionic equation expresses a reaction in terms of the ions that are present in solution a net ionic equation is the chemical equation that remains after the cancellation of the spectator ions. 

Table 1.1 summarizes the solubility patterns of common ionic compounds in water. Notice that all nitrates and all common compounds of the Group 1 metals are soluble so they make useful starting solutions for precipitation reactions. Any spectator ions can be used, provided that they remain in solution and do not otherwise react. For example, Table 1.1 shows that mercury(I) iodide, Hg2I2, is insoluble. It is formed as a precipitate when solutions containing Hg22+ ions and I ions are mixed ... 

The contents of Beaker 1 are mixed with those of Beaker 2. If a reaction takes place, write the net ionic equation and indicate the spectator ions. ... 

Each of the following five procedures results in the formation of a precipitate. For each reaction, write the chemical equations describing the formation of the precipitate the overall equation, the complete ionic equation, and the net ionic equation. Identify the spectator ions. 

According to the ideal stripping model, the incident X + ion collides with a quasi-free H atom while the other H atom in the H2 molecule merely participates as idle spectator to the reaction. The conservation of momentum in the system X +-H requires the secondary ion XH + to be formed with the velocity ... 

However, it is clear here that two of the ions are just spectators that have no influence of the reaction, and could best be removed to give ... 

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