Question: The concentration of a solution of HCl

> Calculate the pH corresponding to each of the following hydrogen ion concentrations, and indicate whether each solution is acidic, basic, or neutral. a. [H+] = 0.00512 M b. [H+] = 3.76 * 10-5 M c. [H+] = 5.61 * 10-10 M d. [H+] = 8.44 * 10-6 M

> Calculate the pH corresponding to each of the hydrogen ion concentrations given below, and indicate whether each solution is acidic or basic. a. [H+] = 4.02 * 10-3 M b. [H+] = 8.99 * 10-7 M c. [H+] = 2.39 * 10-6 M d. [H+] = 1.89 * 10-10 M

> Consider the reaction 2CO(g) + O2(g) ⇌ 2CO2(g) Suppose the system is already at equilibrium, and then an additional mole of CO2(g) is injected into the system at constant temperature. Does the amount of O2(g) in the system increase or decrease? Does th

> How do chemists envision reactions taking place in terms of the collision model for reactions? Give an example of a simple reaction and how you might envision the reaction’s taking place by means of a collision between the molecules.

> For a hydrogen ion concentration of 2.33 * 10-6 M, how many decimal places should we give when expressing the pH of the solution?

> Calculate the [H+] in each of the following solutions, and indicate whether the solution is acidic or basic. a. [OH-] = 2.32 * 10-4 M b. [OH-] = 8.99 * 10-10 M c. [OH-] = 4.34 * 10-6 M d. [OH-] = 6.22 * 10-12 M

> A conjugate acid–base pair consists of two substances related by the donating and accepting of a(n) .

> Of the following acids, which have relatively strong conjugate bases? a. HNO2 b. HCOOH c. HClO4 d. HNO3

> Calculate the concentration of all ions present when 0.160 g of MgCl2 is dissolved in enough water to make 100.0 mL of solution.

> Buffered solutions are mixtures of a weak acid and its conjugate base. Explain why a mixture of a strong acid and its conjugate base (such as HCl and Cl-) is not buffered.

> Why do scientists tend to express the acidity of a solution in terms of its pH, rather than in terms of the molarity of hydrogen ion present? How is pH defined mathematically?

> A buffered solution is prepared containing acetic acid, HC2H3O2, and sodium acetate, NaC2H3O2, both at 0.5 M. Write a chemical equation showing how this buffered solution would resist a decrease in its pH if a few drops of aqueous strong acid HCl solutio

> If 27.5 mL of 3.5 * 10-2 N Ca(OH)2 solution is needed to neutralize 10.0 mL of nitric acid solution of unknown concentration, what is the normality of the nitric acid?

> Which component of a buffered solution is capable of combining with an added strong acid? Using your example from Exercise 60, show how this component would react with added HCl.

> A sodium dihydrogen phosphate solution was prepared by dissolving 5.0 g of NaH2PO4 in enough water to make 500. mL of solution. What are the molarity and normality of the resulting solution?

> Calculate the normality of each of the following solutions. a. 0.50 M acetic acid, HC2H3O2 b. 0.00250 M sulfuric acid, H2SO4 c. 0.10 M potassium hydroxide, KOH

> What two components make up a buffered solution? Give an example of a combination that would serve as a buffered solution.

> According to Arrhenius, produce hydrogen ions in aqueous solution, whereas produce hydroxide ions.

> What minimum volume of 16 M sulfuric acid must be used to prepare 750 mL of a 0.10 M H2SO4 solution?

> How many grams of Ba(NO3)2 are required to precipitate all the sulfate ion present in 15.3 mL of 0.139 M H2SO4 solution? Ba(NO3)2(aq) + H2SO4(aq) BaSO4(s) + 2HNO3(aq)

> What characteristic properties do buffered solutions possess?

> For each of the following solutions, the mass of solute is given, followed by the total volume of the solution prepared. Calculate the molarity of each solution. a. 5.59 g CaCl2; 125 mL b. 2.34 g CaCl2; 125 mL c. 8.73 g CaCl2; 125 mL d. 11.5 g CaCl2;

> When 10. L of water is added to 3.0 L of 6.0 M H2SO4, what is the molarity of the resulting solution? Assume the volumes are additive.

> Calculate the pH of each of the following solutions from the information given. a. [H+] = 3.42 * 10-10 M b. pOH = 5.92 c. [OH-] = 2.86 * 10-7 M d. [H+] = 9.11 * 10-2 M

> How many milliliters of 18.0 M H2SO4 are required to prepare 35.0 mL of 0.250 M solution?

> Calculate the pH of each of the following solutions from the information given. a. [H+] = 4.78 * 10-2 M b. pOH = 4.56 c. [OH-] = 9.74 * 10-3 M d. [H+] = 1.24 * 10-8 M

> Calcium carbonate, CaCO3, can be obtained in a very pure state. Standard solutions of calcium ion are usually prepared by dissolving calcium carbonate in acid. What mass of CaCO3 should be taken to prepare 500. mL of 0.0200 M calcium ion solution?

> The “Chemistry in Focus” segment Garden-Variety Acid– Base Indicators discusses acid–base indicators found in nature. What colors are exhibited by red cabbage juice under acid conditions? Under basic conditions?

> If 10. g of AgNO3 is available, what volume of 0.25 M AgNO3 solution can be prepared?

> How do the components of a conjugate acid–base pair differ from one another? Give an example of a conjugate acid–base pair to illustrate your answer.

> How many moles of the indicated solute does each of the following solutions contain? a. 1.5 L of 3.0 M H2SO4 solution b. 35 mL of 5.4 M NaCl solution c. 5.2 L of 18 M H2SO4 solution d. 0.050 L of 1.1 * 10-3 M NaF solution

> Water is the most common amphoteric substance, which means that, depending on the circumstances, water can behave either as an acid or as a base. Using HF as an example of an acid and NH3 as an example of a base, write equations for these substances reac

> For each of the following solutions, the mass of solute is given, followed by the total volume of the solution prepared. Calculate the molarity of each solution. a. 3.51 g NaCl; 25 mL b. 3.51 g NaCl; 50. mL c. 3.51 g NaCl; 75 mL d. 3.51 g NaCl; 1.00

> Concentrated hydrochloric acid is made by pumping hydrogen chloride gas into distilled water. If concentrated HCl contains 439 g of HCl per liter, what is the molarity?

> Complete the table for each of the following solutions: [H*] pH pOH [OH=] 0.0070 М HNO, 3.0 М КОН

> Choose pairs in which the species listed first is the conjugate base of the species listed second. a. S2-, HS- b. H+, OH- c. HBr, Br- d. NO2-, HNO2

> You add 40.0 mL of water to 60.0 mL of a 2.00 M calcium chloride solution. How many moles of calcium chloride are in the new solution?

> How many moles of each ion are present in 11.7 mL of 0.102 M Na3PO4 solution?

> A solution contains 7.5% by mass NaCl and 2.5% by mass KBr. What mass of each solute is contained in 125 g of the solution?

> What mass of KNO3 is required to prepare 125 g of 1.5% KNO3 solution?

> How many grams of Na2CO3 are contained in 500. g of a 5.5% by mass Na2CO3 solution?

> A sugar solution is prepared in such a way that it contains 10.% dextrose by mass. What quantity of this solution do we need to obtain 25 g of dextrose?

> A certain grade of steel is made by dissolving 5.0 g of carbon and 1.5 g of nickel per 100. g of molten iron. What is the mass percent of each component in the finished steel?

> Calculate the [OH-] in each of the following solutions, and indicate whether the solution is acidic or basic. a. [H+] = 1.02 * 10-7 M b. [H+] = 9.77 * 10-8 M c. [H+] = 3.41 * 10-3 M d. [H+] = 4.79 * 10-11 M

> What is an oxyacid? Write the formulas of three acids that are oxyacids. Write the formulas of three acids that are not oxyacids.

> Calculate the mass, in grams, of NaCl present in each of the following solutions. a. 11.5 g of 6.25% NaCl solution b. 6.25 g of 11.5% NaCl solution c. 54.3 g of 0.91% NaCl solution d. 452 g of 12.3% NaCl solution

> A solution is 0.1% by mass calcium chloride. Therefore, 100. g of the solution contains g of calcium chloride.

> Calculate the hydrogen ion concentration, in moles per liter, for solutions with each of the following pH values. a. pH = 8.34 b. pH = 5.90 c. pH = 2.65 d. pH = 12.6

> An experiment calls for 1.00 g of silver nitrate, but all that is available in the laboratory is a 0.50% solution of AgNO3. Assuming the density of the silver nitrate solution to be very nearly that of water because it is so dilute, determine how many mi

> Calculate the pOH corresponding to each of the pH values listed, and indicate whether each solution is acidic, basic, or neutral. a. pH = 1.02 b. pH = 13.4 c. pH = 9.03 d. pH = 7.20

> What volume of hydrogen chloride gas at STP is required to prepare 500. mL of 0.100 M HCl solution?

> Aqueous ammonia is typically sold by chemical supply houses as the saturated solution, which has a concentration of 14.5 mol/L. What volume of NH3 at STP is required to prepare 100. mL of concentrated ammonia solution?

> Strictly speaking, the solvent is the component of a solution that is present in the largest amount on a mole basis. For solutions involving water, water is almost always the solvent because there tend to be many more water molecules present than molecul

> Calculate the [OH-] in each of the following solutions, and indicate whether the solution is acidic or basic. a. [H+] = 4.01 * 10-4 M b. [H+] = 7.22 * 10-6 M c. [H+] = 8.05 * 10-7 M d. [H+] = 5.43 * 10-9 M

> Organic acids contain the carboxyl group Using acetic acid, CH3-COOH, and propionic acid, CH3CH2-COOH, write equations showing how the carboxyl group enables these substances to behave as weak acids when dissolved in water. `0-H

> Name four strong acids. For each of these, write the equation showing the acid dissociating in water.

> If 500. g of water is added to 75 g of 25% NaCl solution, what is the percent by mass of NaCl in the diluted solution?

> Write the conjugate base for each of the following. a. H3PO4 b. HCO3- c. HF d. H2SO4

> Write the conjugate acid for each of the following. a. NH3 b. NH2- c. H2O d. OH-

> In each of the following chemical equations, identify the conjugate acid–base pairs. a. CH3NH2 + H2O ⇌ CH3NH3+ + OH- b. CH3COOH + NH3 ⇌ CH3COO- + NH4+ c. HF + NH3 ⇌ F- + NH4+

> Suppose that 27.34 mL of standard 0.1021 M NaOH is required to neutralize 25.00 mL of an unknown H2SO4 solution. Calculate the molarity and the normality of the unknown solution.

> When hydrochloric acid, HCl, is added dropwise to a buffered solution, the component of the buffer consumes the added hydrogen ion.

> When sodium hydroxide, NaOH, is added dropwise to a buffered solution, the component of the buffer consumes the added hydroxide ion.

> Calculate the [H+] in each of the following solutions, and indicate whether the solution is acidic, basic, or neutral. a. [OH-] = 7.86 * 10-4 M b. [OH-] = 5.44 * 10-2 M c. [OH-] = 3.19 * 10-3 M d. [OH-] = 2.51 * 10-9 M

> How many milliliters of 0.50 N NaOH are required to neutralize exactly 15.0 mL of 0.35 N H2SO4?

> A buffered solution is one that resists a change in when either a strong acid or a strong base is added to it.

> A solution of phosphoric acid, H3PO4, is found to contain 35.2 g of H3PO4 per liter of solution. Calculate the molarity and normality of the solution.

> Calculate the normality of each of the following solutions. a. 0.134 M NaOH b. 0.00521 M Ca(OH)2 c. 4.42 M H3PO4

> Calculate the normality of each of the following solutions. a. 0.250 M HCl b. 0.105 M H2SO4 c. 5.3 * 10-2 M H3PO4

> The ion-product constant for water, Kw, has the value at 25 °C.

> For each of the following solutions, calculate the normality. a. 25.2 mL of 0.105 M HCl diluted with water to a total volume of 75.3 mL b. 0.253 M H3PO4 c. 0.00103 M Ca(OH)2

> How many equivalents of hydroxide ion are needed to react with 1.53 equivalents of hydrogen ion? How did you know this when no balanced chemical equation was provided for the reaction?

> An acid such as HCl that strongly conducts an electric current when dissolved in water is said to be a(n) acid.

> A solution that contains 1 equivalent of acid or base per liter is said to be a solution.

> What is a standard solution? Describe the steps involved in preparing a standard solution.

> One equivalent of an acid is the amount of the acid required to provide .

> According to the Brønsted–Lowry model, a base is a species that protons.

> According to Arrhenius, bases are species that produce ions in aqueous solution.

> The total acidity in water samples can be determined by neutralization with standard sodium hydroxide solution. What is the total concentration of hydrogen ion, H+, present in a water sample if 100. mL of the sample requires 7.2 mL of 2.5 * 10-3 M NaOH t

> Is it possible for a solution to have [H+] = 0.002 M and [OH-] = 5.2 * 10-6 M at 25 °C? Explain.

> What volume of a 0.500 M NaOH solution would be required to neutralize 40.0 mL of a 0.400 M H2SO4 solution?

> What volume of 0.502 M NaOH solution would be required to neutralize 27.2 mL of 0.491 M HNO3 solution?

> Of the following conditions, which indicate a basic solution? a. pOH = 12.53 b. pH = 3.64 c. pOH < [H1] d. [OH-] > 1.0 * 10-7 M

> Of the following conditions, which indicate an acidic solution? a. pH = 8.95 b. [H+] < 1.0 * 10-7 M c. pOH = 3.46 d. [OH-] = 7.11 * 10-10 M

> Write an equation showing how HCl(g) behaves as an Arrhenius acid when dissolved in water. Write an equation showing how NaOH(s) behaves as an Arrhenius base when dissolved in water.

> What happens to the hydroxide ion concentration in aqueous solutions when we increase the hydrogen ion concentration by adding an acid? What happens to the hydrogen ion concentration in aqueous solutions when we increase the hydroxide ion concentration b

> According to the Brønsted-Lowry model, an acid is a “proton donor” and a base is a “proton acceptor.” Explain.

> Write a chemical equation showing how each of the following species can behave as indicated when dissolved in water. a. O2- as a base b. NH3 as a base c. HSO4- as an acid d. HNO- as an acid

> Generally only the carbonates of the Group 1 elements and the ammonium ion are soluble in water; most other carbonates are insoluble. How many milliliters of 0.125 M sodium carbonate solution would be needed to precipitate the calcium ion from 37.2 mL of

> Write a chemical equation showing how each of the following species can behave as indicated when dissolved in water. a. HSO3- as an acid b. CO32- as a base c. H2PO4- as an acid d. C2H3O2- as a base

> During a summer research internship, you are asked to do lab work and prepare solutions for experiments to be run on samples that will come in from the field. You need to prepare a 0.300 M NaOH solution but only have 6.00 M NaOH on the shelf. What volume

> How much water must be added to 500. mL of 0.200 M HCl to produce a 0.150 M solution? (Assume that the volumes are additive.)

> Suppose 325 mL of 0.150 M NaOH is needed for your experiment. How would you prepare this if all that is available is a 1.01 M NaOH solution?

> How would you prepare 275 mL of 0.350 M NaCl solution using an available 2.00 M solution?

> For convenience, one form of sodium hydroxide that is sold commercially is the saturated solution. This solution is 19.4 M, which is approximately 50% by mass sodium hydroxide. What volume of this solution would be needed to prepare 3.50 L of 3.00 M NaOH

> Many laboratories keep bottles of 3.0 M solutions of the common acids on hand. Given the following molarities of the concentrated acids, determine how many milliliters of each concentrated acid would be required to prepare 225 mL of a 3.0 M solution of t

> A bottle of acid solution is labeled “3 M HNO3.” What are the substances that are actually present in the solution? Are any HNO3 molecules present? Why or why not?

> What is meant by the ion-product constant for water, Kw? What does this constant signify? Write an equation for the chemical reaction from which the constant is derived.

> When 1 mole of gaseous hydrogen chloride is dissolved in enough water to make 1 L of solution, approximately how many HCl molecules remain in the solution? Explain.

> When the volume of a given solution is tripled (by adding water), the new concentration of solute is the original concentration.