The auto-ionization of water is shown in the reaction below. Given that this reaction is endothermic, what is the pH of pure water at 10'C? H,0 H OH AH-55.80 kimol

Write the reaction and the corresponding Kb equilibrium expression for each of the following substances acting as bases in water. a. aniline, C6H5NH2 b. dimethylamine, (CH3)2NH

Write the acid ionization constant expression for the ionization of each of the following monoprotic acids. a. HF (hydrofluoric acid) b. HC2H3O2 (acetic acid)

Novocaine, C13H21O2N2Cl, is the salt of the base procaine and hydrochloric acid. The ionization constant for procaine is 7106. 15 a solution of novocaine acidic or basic? What are [H3O+], [OH-], and pH of a 2.0% solution by mass of novocaine, assuming that the density of the solution is 1.0 g/mL.

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.

2. The cyanide ion, CN−, accepts a proton from water to form HCN. Is CN− a Bronsted acid or base or is it amphiprotic? acid base amphiprotic

Aluminum chloride, AlCl3, reacts with trimethyl-amine, N(CH3)3. What would you guess to be the product of this reaction? Explain why you think so. Describe the reaction in terms of one of the acid base concepts. Write an appropriate equation to go with this description. Which substance is the acid according to this acidbase concept? Explain.

Strong Acids, Weak Acids, and pH Two 0.10-mol samples of the hypothetical monoprotic acids HA(aq) and HB(aq) are used to prepare 1.0-L stock solutions of each acid. a Write the chemical reactions for these acids in water. What are the concentrations of the two acid solutions? b One of these acids is a strong acid, and one is weak. What could you measure that would tell you which acid was strong and which was weak? c Say that the HA(aq) solution has a pH of 3.7. Is this the stronger of the two acids? How did you arrive at your answer? d What is the concentration of A(aq) in the HA solution described in part c? e If HB(aq) is a strong acid, what is the hydronium-ion concentration? f In the solution of HB(aq), which of the following would you expect to be in the greatest concentration: H3O+(aq), B(aq), HB(aq), or OH(aq)? How did you decide? g In the solution of HA(aq), which of the following would you expect to be in the greatest concentration: H3O+(aq), A+(aq), HA(aq), or OH(aq)? How did you decide? h Say you add 1.0 L of pure water to a solution of HB. Would this water addition make the solution more acidic, make it less acidic, or not change the acidity of the original solution? Be sure to fully justify your answer. i You prepare a 1.0-L solution of HA. You then take a 200-mL sample of this solution and place it into a separate container. Would this 200 mL sample be more acidic, be less acidic, or have the same acidity as the original 1.0-L solution of HA(aq)? Be sure to support your answer.

To measure the relative strengths of bases stronger than OH, it is necessary to choose a solvent that is a weaker acid than water. One such solvent is liquid ammonia. (a) Write a chemical equation for the autoionization of ammonia. (b) What is the strongest acid and base that can exist in liquid ammonia? (c) Will a solution of HCI in liquid ammonia be a strong electrical conductor, a weak conductor, or a nonconductor? (d) Oxide ion (O2) is a stronger base than the amide ion (NH2). Write an equation for the reaction of O2 with NH3 in liquid ammonia. Will the equilibrium favor products or reactants?

C6H4NH2COOH, para-aminobenzoic acid (PABA), is used in some sunscreen agents. Calculate the concentrations of hydronium ion and para-aminobenzoate ion, C6H4NH2COO, in a 0.080 M solution of the acid. The value of Ka is 2.2 105.