3. Papaverine hydrochloride (pap HCI), 2 salt of a weak base and a strong acid, is a drug used as a muscie relaxant. It is a weak acid. At 25° C, a 0.205 M solution of papHC has a pH of 3.31. Compute the K of papHCL.

. Using Fig. 16.3, list the approximate pH value of live “everyday” solutions. How do the familiar properties (such as the sour taste for acids) of these solutions correspond to their indicated pH?

Why have chemists not tabulated the fraction ionized for different acids? Such a table would make problems such as calculating the pH of an acid solution quite simple.

For oxyacids, how does acid strength depend on a. the strength of the bond to the acidic hydrogen atom? b. the electronegativity of the element bonded to the oxygen atom that bears the acidic hydrogen? c. the number of oxygen atoms? How does the strength of a conjugate base depend on these factors? What type of solution forms when a nonmetal oxide dissolves in water? Give an example of such an oxide. What type of solution forms when a metal oxide dissolves in water? Give an example of such an oxide.

A solution is made by dissolving 15.0 g sodium hydroxide in approximately 450 mL water. The solution becomes quite warm, but after it is allowed to return to room temperature, water is added to bring the volume to 500.0 mL of solution. (a) Calculate the pH and pOH in the final solution. (b) Why would we wait for it to return to room temperature? (c) If the mass of the water used to initially dissolve the sodium hydroxide were exactly 450 g and the temperature of the water increased by 8.865 C, how much heat was given off by the dissolution of 15.0 g of solute? Assume the specific heat of the solution is 4.184 J/g. K. What is the molar heat change for the dissolution of sodium hydroxide (known as the enthalpy of solution, Hsol)?

1. Which of the following can act as a Lewis acid? (Hint : In each case, draw the Lewis electron dot structure of the molecule or ion. Are there lone pairs of electrons on the central atom? If so, it can be a Lewis base. Does the central atom lack an electron pair? If so, it can behave as a Lewis acid.) PH3 BCl3 H2S HS−

. Consider 0.25 M solutions of the following salts: NaCl. RbOC1, KI, Ba(ClO4),, and NH4NO3. For each salt, indicate whether the solution is acidic, basic, or neutral.

What is the pH of a solution obtained by mixing 235 mL of NaOH with a pH of 11.57 and 316 mL of Sr(OH)2 with a pH of 12.09? Assume that volumes are additive.

The weak base, CIO (hypochlorite ion), is used in the form of NaCIO as a disinfectant in swimming pools and water treatment plants. What are the concentrations of HCIO and OH and the pH of a 0.015 M solution of NaCIO?

Find [H+] and the pH of the following solutions. (a) A 456-mL sample of a 12.0% (by mass) solution of HNO3(d=1.00g/mL). What is the pH of 10.0 mL of the same sample? (b) A solution made up of 1.0 g of HCI dissolved in enough water to make 1.28 L of solution. What is the pH of the solution? If the same mass of HCI is dissolved in enough water to make 128 mL of solution, what would the pH be?