A Solution Contains [Ba²⁺] = 5

question 45

Multiple Choice

A solution contains [Ba²⁺] = 5.0 × 10^-5 M, [Ag⁺] = 3.0 × 10^-5 M, and [Zn²⁺] = 2.0 × 10^-7 M. Sodium oxalate is slowly added so that [C₂O₄^2-] increases.
Salt BaC₂O₄   ZnC₂O₄   Ag₂C₂O₄
Ksp 1.5 × 10^-8   1.35 × 10^-9  1.1 × 10^-11
Which one of the oxalates precipitates first?

• A) BaC₂O₄
• B) Na₂C₂O₄
• C) ZnC₂O₄
• D) Ag₂C₂O₄
• E) ZnC₂O₄ and Ag₂C₂O₄ precipitate together

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Definitions:

Myelination

The process of forming a myelin sheath around neurons, improving the speed and efficiency of electrical signal transmission in the nervous system.

Schwann Cells

A type of glial cell that myelinates the axons of the peripheral nervous system, enabling fast electrical impulses.

Nodes Of Ranvier

Gaps in the myelin sheath of axons that facilitate rapid signal transmission via saltatory conduction.

Hyperpolarization

A change in a cell's membrane potential, making it more negative, and thus further from initiating an action potential.