The preparations of two aqueous solutions are described in the table below. For each solution, write the chemical formulas of the major species present at equilibrium. You can leave out water itself. Write the chemical formulas of the species that will act as acids in the 'acids' row, the formulas of the species that will act as bases in the 'bases' row, and the formulas of the species that will act as neither acids nor bases in the 'other' row. You will find it useful to keep in mind that NH, is a weak base. 0.7 mol of HBr is added to 1.0 L of a 0.7M NH3 solution. acids: HBr, NH bases: X other: Br 0.2 mol of HNO3 is added to acids: NH 1.0 L of a solution that is 0.6M in both NH3 and NHCI. ✔ bases: NH, other: NO,, Br

When perchloric acid ionizes, it makes the perchlorate ion, ClO4. Draw the Lewis electron dot symbol for the perchlorate ion.

Each box represents an acid solution at equilibrium. Squares represent H+ ions, and circles represent the anion. Water molecules are not shown. Which figure represents a strong acid? Which figure is a weak acid?

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.

How would you compare the strengths of two weak acids experimentally? By looking up information in a table or a handbook?

Classify each of the following statements as true or false: aAll Brnsted-Lowry acids are Arrhenius acids. bAll Arrhenius bases are Brnsted-Lowry bases, but not all Brnsted-Lowry bases are Arrhenius bases. c HCO3 is capable of being amphoteric. d HS is the conjugate base of S2. eIf the species on the right side of an ionization equilibrium are present in greater abundance than those on the left, the equilibrium is favored in the forward direction. f NH4+ cannot act as a Lewis base. gWeak bases have a weak attraction for protons. hThe stronger acid and the stronger base are always on the same side of a proton transfer reaction equation. iA proton transfer reaction is always favored in the direction that yields the stronger acid. jA solution with pH=9 is more acidic than one with pH=4. kA solution with pH=3 is twice as acidic as one with pH=6. lA pOH of 4.65 expresses the hydroxide ion concentration of a solution in three significant figures.

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.

Arsenic acid (H3AsO4) is a moderately weak triprotic acid. Write equations showing its stepwise dissociation. Which of the three anions formed in these reactions will be the strongest Brnsted base? Which will be the weakest Brnsted base? Explain your answers.

Explain why equilibrium arrows are used in the ionization equations for some acids.