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:

Secondary A2 Component

A component that is not primary but serves as an additional or supplementary element in various systems or models.

Primary A1 Component

The initial segment of the auditory cortex that processes basic auditory information.

Sometimes-Opponent-Process Theory

A theory suggesting emotional reactions are followed by opposite emotional states; initially applied to psychological explanations of drug addiction.

Unconditioned Stimulus

A stimulus that naturally triggers a response without the need for prior learning.