What is the most soluble salt of the following set? A) Al(OH)_3 with K_sp = 1.9

Question

What is the most soluble salt of the following set? A) Al(OH)_3 with K_sp = 1.9 times 10^-33 B) Fe(OH)_3 with K_sp = 2.6 times 10^-39 C) Sn(OH)_2 with K_sp = 1.6 times 10^-19 D) AgCN with K_sp = 6.0 times 10^-17 In which of the following solutions would solid PbCl_2 be expected to be the least soluble at 25 degree C? A) 0.1 M KNO_3 B) 0.1 M HCl C) 0.1 M NaCl D) 0.1 M CaCl_2 Which statement is true? A) oxidation occurs at the anode in a galvanic cell and at the cathode in an electrolytic cell. B) Oxidation occurs at the cathode in a galvanic cell and at the anode in an electrolytic cell. C) The cathode is positive for a galvanic cell and negative for an electrolytic cell. D) Electrons flow through the external circuit to the cathode in a galvanic cell and to the anode in an electrolytic cell What is the shorthand notation that represents the following galvanic cell reaction? 2 Fe^2+ (aq) + Cl_2(g) rightarrow 2 Fe^3+(aq) + 2 Cl^-(aq) A) Pt(s)|Fe^3+(aq), Fe^2+(aq), Cl_2(g)||Cl^-(aq)|C(s) B) Fe^2+ (aq)| Fe^3+(aq)||Cl_2(g)| Cl^- (aq) C) Pt(s)|Fe^2+(aq), Fe^3+(aq)||Cl_2(g)|Cl^-(aq)|C(s) Fe(s)|Fe^2+(aq)||Fe^3+(aq)Cl_2(g)|Cl^-(aq)|C(s) For the reaction 2 Al(s) + 3 Co^2+(aq) rightarrow 2 A1^3+(aq) + 3Co(s), delta G degree is -799 kJ. What is E degree for a standard cell based on this reaction? A) +8.28 V B) +2.76 V C) +4.14 V D) +1.38 V

Explanation / Answer

7.option D is correct.

If All salts have the same number of ions so you just compare the Ksp. The salt with the largest Ksp is most
soluble. If they didn't have the same number of ions then you would need to calculate molar solubility.

8.option D is correct.

PbCl2(s) <-------> Pb2+(aq) + 2Cl-(aq)
Which has an equilibrium constant of Ksp.

Ksp = [Pb2+][Cl-]^2
and molar solubility of the overall compound, s, is:
Ksp = (s)(2s)^2 = (s)(4s^2) = 4s^3

In this case, it is important to note that the equilibrium (which directly affects the ability of the PbCl2 to dissolve) is affected by pre-existing Cl- and Pb2+ concentrations. The higher the concentration of either of these ions, the less able the PbCl2 will be able to dissolve. This is known as the COMMON ION EFFECT: pre-exisiting ions of the same nature as the ions in the actual compound we are trying to dissolve will suppress the equilibrium, keeping more of the target compound not dissolved.

9.option D is correct.

The anode is the electrode where oxidation (loss of electrons) takes place; in a galvanic cell, it is the negative electrode, as when oxidation occurs, electrons are left behind on the electrode.

The direction of electron flow in electrolytic cells, however, may be reversed from the direction of spontaneous electron flow in galvanic cells, but the definition of both cathode and anode remain the same, where reduction takes place at the cathode and oxidation occurs at the anode.

10.option C is correct.

Related Questions

Navigate

• Browse (All)
• Browse W
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.