If we can find the equilibrium constant for the reaction, the process is straightforward. The acetate ion behaves as a base in this reaction; hydroxide ions are a product. We determine K b as follows:. Check Your Learning What is the pH of a 0. Use 4. In a solution of a salt formed by the reaction of a weak acid and a weak base, to predict the pH, we must know both the K a of the weak acid and the K b of the weak base.
Determining the Acidic or Basic Nature of Salts Determine whether aqueous solutions of the following salts are acidic, basic, or neutral:. Solution Consider each of the ions separately in terms of its effect on the pH of the solution, as shown here:. The solution is neutral. The solution will be acidic.
Check Your Learning Determine whether aqueous solutions of the following salts are acidic, basic, or neutral:. If we measure the pH of the solutions of a variety of metal ions we will find that these ions act as weak acids when in solution. The aluminum ion is an example. However, in this case, the hydrated aluminum ion is a weak acid Figure 2 and donates a proton to a water molecule. Thus, the hydration becomes important and we may use formulas that show the extent of hydration:.
As with other polyprotic acids, the hydrated aluminum ion ionizes in stages, as shown by:. Note that some of these aluminum species are exhibiting amphiprotic behavior, since they are acting as acids when they appear on the left side of the equilibrium expressions and as bases when they appear on the right side.
However, the ionization of a cation carrying more than one charge is usually not extensive beyond the first stage. Additional examples of the first stage in the ionization of hydrated metal ions are:. Solution In spite of the unusual appearance of the acid, this is a typical acid ionization problem. The reaction shifts to the right to reach equilibrium. Determine x and equilibrium concentrations. Use the table: Solve for x and the equilibrium concentrations. The constants for the different stages of ionization are not known for many metal ions, so we cannot calculate the extent of their ionization.
However, practically all hydrated metal ions other than those of the alkali metals ionize to give acidic solutions. Ionization increases as the charge of the metal ion increases or as the size of the metal ion decreases. The neutralization that occurs when aqueous solutions of acids and bases are combined results from the reaction of the hydronium and hydroxide ions to form water.
Some salts formed in neutralization reactions may make the product solutions slightly acidic or slightly basic. Solutions that contain salts or hydrated metal ions have a pH that is determined by the extent of the hydrolysis of the ions in the solution. The pH of the solutions may be calculated using familiar equilibrium techniques, or it may be qualitatively determined to be acidic, basic, or neutral depending on the relative K a and K b of the ions involved.
Answers to Chemistry End of Chapter Exercises 2. Skip to content Chapter Acid-Base Equilibria. Learning Objectives By the end of this section, you will be able to:. Predict whether a salt solution will be acidic, basic, or neutral Calculate the concentrations of the various species in a salt solution Describe the process that causes solutions of certain metal ions to be acidic. Often, solutions are either too acidic or too basic, so a reaction must take place in order to achieve neutralization.
That neutralization leads to the formation of water and a salt. It is also a broader term that categorizes the compound that is created in the reaction between an acid and a base. In this type of neutralization reaction, the acids and bases are the reactants, since they are the materials that will react to form a new solution. The products are the water and salt, since they have been created following the reaction.
These conditions are caused by an excess of stomach acids. In order to neutralize that, you might take an antacid, which is often comprised of a bicarbonate, which is a base. In this reaction, the base in the antacid and the hydrochloric acid in the stomach are the reactants, and they combine to form the products salt, water and carbon dioxide.
Those products help neutralize the acids in your stomach and lessen the painful symptoms of heartburn. Farmers and gardeners also frequently use neutralization equations to help their plants flourish.
Some soil is too acidic for certain plants to thrive, so gardeners add a fertilizer that contains a base like lime in order to neutralize the soil. Problem: Calculate the pH titration of 50 mL of 0. Which of the following compounds is insoluble? Also check sig figs. Ion Concentrations 1. A solution is prepared by dissolving 5. Please Help me with my chemistry Review I have a test tommorow? Please help me with my review my test average is low and i need at least a b to pass the class for the six weeks I am freaking out!!!!
I care more about showing work i don't want answers I. After the reaction is complete, calculate the amount of precipitate that formed.
Chloroform CHCl is an important solvent. It is produced by a reaction between methane and chlorine. How many g CH4 are needed to produce A solution of 0. Why won't we get FeCl3? What is the volume, in liters, of 2. What is the percent composition of. Hi Dr. I have read the material in my textbook and even took out a chemistry books for the "Utterly Confused" to try to figure this out. Answer in units of g.
How much Na3PO4 can be prepared by. Supposing we allow g of phosphorus to react with excess oxygen which forms tetraphosphorus decoxide P4O10 in In the second step reaction, a Work out the mass of H3PO4 obtained?
Predict these reaction products. If a reaction takes place, balance the reaction if needed. If no reaction takes place then write no reaction. Starting with equal concentrations of all solutes, predict the direction in which the following reaction will proceed. A mL solution has a chloride concentration of 0.
This solution was prepared by adding solid FeCl3 to water. How many grams of FeCl3 are required? How many grams of NaOH Mr 40 must be added to ml of 0. I know I'm using HH-equation. What if when I find my product, I get the same compound as I did in my reactant? Then something is wrong. In this case, FeCl3 and HCl usually don't react.
Phosphoric acid, H3PO4, has some important applications. It can be used to produce fertilizers and it is present in soft drinks. What is the concentration of Fe III with a stock concentration of.
I got. A reaction occurs that produces a precipitate. How many grams of precipitate are produced in the reaction? Determine the volume of 2. What was the concentration of the unknown H3PO4 solution answer in M. So I have had several homework problem like this and managed to solve them easily, but these two problems I cannot get the correct answer for. Using a Table of thermodynamic data, calculate the change in Gibbs free energy for each of the following.
Explain with chemical equation.
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