A student mixes 10.00 mL of a 0.00300 M solution of iron(III) nitrate with 2.00 mL of a 0.00100 M potassium thiocyanate solution and 8.00 mL of water. Before any reaction begins, what are the initial concentrations of iron(III) ion and thiocyanate ion?     [Fe3+]=      [SCN−]=

The Behavior of Substances in Water Part 1: a Ammonia, NH3, is a weak electrolyte. It forms ions in solution by reacting with water molecules to form the ammonium ion and hydroxide ion. Write the balanced chemical reaction for this process, including state symbols. b From everyday experience you are probably aware that table sugar (sucrose), C12H22O11, is soluble in water. When sucrose dissolves in water, it doesnt form ions through any reaction with water. It just dissolves without forming ions, so it is a nonelectrolyte. Write the chemical equation for the dissolving of sucrose in water. c Both NH3 and C12H22O11 are soluble molecular compounds, yet they behave differently in aqueous solution. Briefly explain why one is a weak electrolyte and the other is a nonelectrolyte. d Hydrochloric acid, HCl, is a molecular compound that is a strong electrolyte. Write the chemical reaction of HCl with water. e Compare the ammonia reaction with that of hydrochloric acid. Why are both of these substances considered electrolytes? f Explain why HCl is a strong electrolyte and ammonia is a weak electrolyte. g Classify each of the following substances as either ionic or molecular. KCl NH3 CO2 MgBr2 HCl Ca(OH)2 PbS HC2H3O2 h For those compounds above that you classified as ionic, use the solubility rules to determine which are soluble. i The majority of ionic substances are solids at room temperature. Describe what you would observe if you placed a soluble ionic compound and an insoluble ionic compound in separate beakers of water. j Write the chemical equation(s), including state symbols, for what happens when each soluble ionic compound that you identified above is placed in water. Are these substances reacting with water when they are added to water? k How would you classify the soluble ionic compounds: strong electrolyte, weak electrolyte, or nonelectrolyte? Explain your answer. l Sodium chloride, NaCl, is a strong electrolyte, as is hydroiodic acid, HI. Write the chemical equations for what happens when these substances are added to water. m Are NaCl and HI strong electrolytes because they have similar behavior in aqueous solution? If not, describe, using words and equations, the different chemical process that takes place in each case. Part 2: You have two hypothetical molecular compounds, AX and AY. AX is a strong electrolyte and AY is a weak electrolyte. The compounds undergo the following chemical reactions when added to water. AX(aq)+H2O(l)AH2O+(aq)+X(aq)AY(aq)+H2O(l)AH2O+(aq)+Y(aq) a Explain how the relative amounts of AX(aq) and AY(aq) would compare if you had a beaker of water with AX and a beaker of water with AY. b How would the relative amounts of X(aq) and Y(aq) in the two beakers compare? Be sure to explain your answer.

A student is asked to identify the metal nitrate present in an aqueous solution. The cation in the solution can be either Na+, Ba2+, Ag+, or Ni2+. Results of solubility experiments are as follows: unknown + chloride ions—no precipitate unknown + carbonate ions—precipitate unknown + sulfate ions—precipitate What is the cation in the solution?

Separate samples of a solution of an unknown soluble ionic compound are treated with KCl, Na2SO4, and NaOH. A precipitate forms only when Na2SO4 is added. Which cations could be present in the unknown soluble ionic compound?

4-33 When a solution of hydrochloric acid, HCl, is added to a solution of sodium sulfite, Na.2S03, sulfur dioxide gas is released from the solution. Write a net ionic equation for this reaction. An aqueous solution of HCl contains H+ and Cl- ions, and Na2SO3 exists as dissociated ions in aqueous solution.

According to the Resource Conservation and Recovery Act (RCRA), waste material is classified as toxic and must be handled as hazardous if the lead concentration exceeds 5 mg/L. By adding chloride ion, the lead ion will precipitate as PbCl2, which can be separated from the liquid portion. Once the lead has been removed, the rest of the waste can be sent to a conventional waste treatment facility. How many grams of sodium chloride must be added to 500 L of a waste solution to reduce the concentration of the Pb2+ ion from 10 to 5 mg/L?

Relative solubilities of salts in liquid ammonia can differsignificantly from those in water. Thus, silver bromide issoluble in ammonia, but barium bromide is not (thereverse of the situation in water). Write a balanced equation for the reaction of anammonia solution of barium nitrate with an ammoniasolution of silver bromide. Silver nitrate is soluble inliquid ammonia. What volume of a 0.50 M solution of silver bromidewill react completely with 0.215 L of a 0.076 M solutionof barium nitrate in ammonia? What mass of barium bromide will precipitate fromthe reaction in part (b)?

An aqueous sample is known to contain either Mg2+ or Ba2+ ions. Treatment of the sample with Na2CO3 produces a precipitate, but treatment with ammonium sulfate does not. Use the solubility rules (see Table 4.1) to determine which cation is present.

Write the net ionic equation for the reaction, if any, that occurs on mixing (a) solutions of sodium hydroxide and magnesium chloride. (b) solutions of sodium nitrate and magnesium bromide. (c) magnesium metal and a solution of hydrochloric acid to produce magnesium chloride and hydrogen. Magnesium metal reacting with HCl.

A student set up an experiment for six different trials of the reaction between 1.00-M aqueous acetic acid, CH3COOH, and solid sodium hydrogen carbonate, NaHCO3. CH3COOH(aq) + NaHCO3(s) NaCH3CO2(aq) + CO2(g) + H2O() The volume of acetic acid was kept constant, but the mass of sodium bicarbonate increased with each trial. The results of the tests are shown in the figure. (a) In which trial(s) is the acetic acid the limiting reactant? (b) In which trial(s) is sodium bicarbonate the limiting reactant? (c) Explain your reasoning in parts (a) and (b).