Gastric juice, the digestive fluid produced in the stomach, contains hydrochloric acid, HCl. Milk of Magnesia, a suspension of solid Mg(OH)2 in an aqueous medium, is sometimes used to neutralize excess stomach acid. Write a complete balanced equation for the neutralization reaction, and identify the conjugate acid-base pairs.

Which of the following conditions indicate an acidic solution? pH = 3.04 (H+| > 1.0 X IO’7 A/ pOH = 4.51 |OH-J = 3.21 X 10"12 M

A Liquid HF undergoes an autoionization reaction: 2HFH2F++F (a) Is KF an acid or a base in this solvent? (b) Perchloric acid, HCIO4, is a strong acid in liquid HF. Write the chemical equation for the ionization reaction. (c) Ammonia is a strong base in this solvent. Write the chemical equation for the ionization reaction. (d) Write the net ionic equation for the neutralization of perchloric acid with ammonia in this solvent.

Follow the directions of Question 19 for the following acids: (a) hypochlorous acid (b) formic acid, HCHO2 (c) acetic acid, HC2H3O2 (d) hydrobromic acid (e) sulfurous acid

Students are often surprised to learn that organic acids, such as acetic acid, contain OH groups. Actually, all oxyacids contain hydroxyl groups. Sulfuric acid, usually written as H2SO4, has the structural formula SO2(OH)2, where S is the central atom. Identify the acids whose structural formulas are shown below. Why do they behave as acids, while NaOH and KOH are bases? a. SO(OH)2 b. ClO2(OH) c. HPO(OH)2

Without writing an equation, specify the molecular ratio in which each of the following acidbase pairs will react. a. HCl and KOH b. H2CO3 and KOH c. HCl and Ca(OH)2 d. H2CO3 and Ca(OH)2

The pH of a 0.10-M solution of propanoic acid, CH3CH2COOH, a weak organic acid, is measured at equilibrium and found to be 2.93 at 25 °C. Calculate the Ka of propanoic acid.

Acids You make a solution by dissolving 0.0010 mol of HCl in enough water to make 1.0 L of solution. a Write the chemical equation for the reaction of HCl(aq) and water. b Without performing calculations, give a rough estimate of the pH of the HCl solution. Justify your answer. c Calculate the H3O+ concentration and the pH of the solution. d Is there any concentration of the base OH present in this solution of HCl(aq)? If so, where did it come from? e If you increase the OH concentration of the solution by adding NaOH, does the H3O+ concentration change? If you think it does, explain why this change occurs and whether the H3O+ concentration increases or decreases. f If you were to measure the pH of 10 drops of the original HCl solution, would you expect it to be different from the pH of the entire sample? Explain. g Explain how two different volumes of your original HCl solution can have the same pH yet contain different moles of H3O+. h If 1.0 L of pure water were added to the HCl solution, would this have any impact on the pH? Explain.

Lactic acid, HC3H5O3, is a weak acid; write an equation for its ionization in aqueous solution. If 0.15 M solution of lactic acid has pH = 2.34, calculate the molar concentration of H3O+in the solution. What are the Ka of lactic acid and the degree of ionization of the acid?

Acidity of a solution is determined by the concentration H of hydrogen ions in the solution (measured in moles per liter of solution). Chemists use the negative of the logarithm of the concentration of hydrogen ions to define the pH scale. pH = − log H Solution A has a pH value of 5.6 and solution B has a pH value of 2.7. Compare the acidity of the two solutions. a) Solution A is more acidic by a factor of 2.07b) Solution B is more acidic by a factor of 794.33c) Solution A is more acidic by a factor of 794.33d) Solution A is more acidic by a factor of 2.90