Writing Equations for Aqueous Ionic Reactions

SAMPLE PROBLEM 4.2 Determining the Molarity of Ions in an Aqueous 

Problem Nitric acid is a major chemical in the fertilizer and explosives industries. In aqueous solution, each molecule dissociates and the H becomes a solvated ion. What is the molarity of in 1.4 A/ nitric acid  

Plan We know the molarity of acid (1.4 M), so we just need the formula to find the number of moles of aq) present in 1 L of solution. 

Solution Nitrate ion is N03, so nitric acid is HNO3. Thus, 1 mol of aq) is released per mole of acid  

Water plays an active role in dissolving ionic compounds because it consists of polar molecules that are attracted to the ions. When an ionic compound dissolves in water, the ions dissociate from each other and become solvated by water molecules. Because the ions are free to move, their solutions conduct electricity. Water also dissolves many covalent substances with polar bonds. It interacts with some H-containing molecules so strongly it breaks their bonds and dissociates them into IT faq) ions and anions. In water, the ion is bonded to an H2O, forming HaO .  

FOLLOW-UP PROBLEM 4.2 How many moles of H (aif) are present in 451 mL of 3.20 M hydrobromic acid  

---

EXAMPLE 7.11 Writing Equations for Acid-Base Reactions Write a molecular and net ionic equation for the reaction between aqueous HNO3 and aqueous Ca(OH)2. ... 

Self-Test 12.9A Which metal, zinc or nickel, is the stronger reducing agent in aqueous solution under standard conditions Evaluate the standard emf of the appropriate cell, specify the cell with a cell diagram, and write the net ionic equation for the spontaneous reaction. 

Give balanced ionic equations for the following reactions in aqueous solution. If a reaction does not occur, write NR. Indicate precipitates by J. and gases by f. 

Write both an ionic equation and a net ionic equation for the neutralization reaction of aqueous HBr and aqueous Ba(OH)2. 

The properties of ionic compounds in solution are actually the properties of the individual ions themselves (Figure 9.1). These compounds are called strong electrolytes because their solutions conduct electricity well. For example, an aqueous solution of sodium chloride consists essentially of sodium ions and chloride ions in water. A similar solution of calcium chloride consists of calcium ions and chloride ions in water. If either solution is treated with a solution containing silver ions, the chloride ions will form silver chloride, which is insoluble. The chloride ions act independently of the cation that is also present, regardless of whether it is sodium ion, calcium ion, or any other ion. Because the properties of the compound are the properties of the component ions, we need to learn to write equations for only the ions that react, omitting the ions that remain unchanged throughout the reaction (Section 9.2). 

Write the net ionic equation for a chemical reaction that occurs in an aqueous solution and produces water. (10.3)... 

The net ionic equation forthe aqueous neutralization reaction between acetic acid and sodium hydroxide is different from that for the reaction between hydrochloric acid and sodium hydroxide. Explain by writing balanced net ionic equations. 

In the laboratory, students often learn to analyze mixtures of the common positive and negative ions, separating and confirming the presence of the particular ions in the mixture. One of the first steps in such an analysis is to treat the mixture with hydrochloric acid, which precipitates and removes silver ion, lead(II) ion, and mercury(I) ion from the aqueous mixture as the insoluble chloride salts. Write balanced net ionic equations for the precipitation reactions of these three cations with chloride ion. 

Without first writing a full molecular or ionic equation, write the net ionic equations for any precipitation reactions that occur when aqueous solutions of the following compounds are mixed. If no reaction occurs, so indicate. 

Write the net ionic equation for the precipitation reaction that occurs when aqueous solutions of silver nitrate and potassium phosphate are mixed. 

Write balanced molecular and net ionic equations for the following reactions, and identify the gas formed in each (a) solid cadmium sulfide reacts with an aqueous solution of sulfuric add (b) solid magnesium carbonate reacts with an aqueous solution of perchloric add. 

Frequently, the compounds involved in aqueous chemistry are ionic, as is true for both HNO3 and NH4NO3 in this example. These ionic compounds dissociate when they dissolve in water, so the actual solution does not contain intact molecules of these compounds. This dissociation is emphasized if we write the total ionic equation rather than the molecular equation. This form emphasizes what is actually present in the reacting mixture by writing dissociated compounds as separated ions in the solution. The total ionic equation for our example reaction from above is thus... 

Write the net ionic equation by eliminating those ions that remain the same on both sides of the equation. SKILLBUILDER 7.11 Writing Equations for Acid-Base Write a molecular and net ionic equation for the reactioi FOR MORE PRACTiCE Example 7.21 Problems 77, 7< 2 H (aq) + 2 OH (aq) 2 H20(/) or simply H+ aq) + OH-(aq) H20(/) Reactions a that occurs between aqueous H2SO4 and aqueous KOH. 3, 79,80. 

Write the formula equation, the overall ionic equation, and the net ionic equation for the neutralization reaction involving aqueous solutions of H3PO4 and Mg(OH)2. Assume that the solutions are sufficiently dilute so that no precipitates form. 

Write a balanced net ionic equation for the reaction of each of the fid-lowing aqueous solutions with H+ ions. 

Self-Test I.2A Write the net ionic equation for the reaction in Fig. 1.1, in which aqueous solutions of colorless silver nitrate and yellow potassium chromate react to give a precipitate of red silver chromate. 

Self-Test I.2B The mercury(I) ion, Hg22+, consists of two Hg+ ions joined together. Write the net ionic equation for the reaction in which colorless aqueous solutions of mercury(I) nitrate, Hg2(N03)2, and potassium phosphate, K3P04, react to give a white precipitate of mercurv(I) phosphate. 

---