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1, Which of the following shorthand galvanic cell notations for the zinc – copper standard cell is correct?                        Cu2+  +  Zn  →  Zn2+  +  Cu (a) Cu2+ | Cu || Zn | Zn2+                                           (b) Cu2+ | Cu || Cu | Cu2+ (c) Cu2+ | 2e– || 2e– | Zn                                            (d) Zn | Zn2+ || Cu2+ | Cu (e) Zn | Cu2+ || Zn2+ | Cu

10. In an electrolytic cell, the electrode that acts as a source of electrons to the solution is                called the __________; the chemical change that occurs at this electrode is called                __________.                (a) anode, oxidation                                                     (b) anode, reduction                (c) cathode, oxidation                                                  (d) cathode, reduction                (e) Cannot answer unless we know the species being oxidized and reduced

90% of deaf individuals are born to hearing parents.

19. What is the hydrogen ion concentration in a solution having a pOH of 3.62?         a) 2.6 x 10-11 M         b) 4.2 x 10-11 M         c) 3.8 x 10-4  M         d 3.8 x 10-5  M         e) 5.1 x 10-10 M

Which acid has the strongest conjugate base?A. HClB. HNO₃C. HFD. HClO₄

23. Calculate the solubility product constant for aluminum hydroxide (Al(OH)3. Its molar solubility is     2.9 x 10–9 mole per liter at 25°C.           (a) 9.8 x 10–26                        (b) 4.9 x 10–26                        (c) 7.1 x 10–35           (d) 2.1 x 10–34                        (e) 1.9 x 10–33

For a saturated solution of PbI₂:PbI₂(s) ⇌ Pb²⁺(aq) + 2I⁻(aq)The Ksp expression is:A. [Pb²⁺][I⁻]B. [Pb²⁺]²[I⁻]C. [Pb²⁺][I⁻]²D. [PbI₂]

A 0.10 M solution of ammonium chloride (NH₄Cl) is prepared. Given that Kb for NH₃ is 1.8 × 10⁻⁵, what is the approximate pH of the solution?A. 4.63 B. 7.00 C. 9.37 D. 11.13Hint: NH₄⁺ is a weak acid. First calculate Ka = Kw/Kb.

10. In the reaction BF3  + F- —>  BF4-,   F- is acting as what type of base?a)Arrhenius onlyb)Bronsted-Lowry onlyc)Lewis onlyd)Arrhenius, Bronsted-Lowry, and Lewise)Arrhenius and Bronsted

6. Which response includes all the following salts that will produce basic or acidic        solutions by hydrolyzing water, and no others.       I. KCN       II. NaF       III. Na2CO3    IV. KCl       V. NH4Br       a) I, III,  and IV       b) II, III, and V       c) II, IV, and V       d) I, II, III, and V        e) I, IV, and V