If a Solution Is Prepared by Dissolving 1

question 46

Multiple Choice

If a solution is prepared by dissolving 1.6 mol Na₂CrO₄ in 1.0 L of a buffer at pH 8.24, what will be [Cr₂O₇^2-] in the solution? The resultant equilibria are: HCrO₄^- ⇌ H⁺ + CrO₄^2-   Ka = 3.2 × 10^-7
2 HCrO₄^- ⇌ Cr₂O₇^2-+ H₂O   K = 33

• A) 9.9 × 10^-5 M
• B) 2.9 × 10^-28 M
• C) 8.9 × 10^-9 M
• D) 8.6 × 10² M
• E) 2.8 × 10^-2 M

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Definitions:

Direct Material Cost

The expense of fundamental materials directly utilized in the production of a product.

Product Cost

The total amount of costs directly and indirectly involved in manufacturing a product or delivering a service.

Variable Costing

A costing method that includes only variable manufacturing costs—direct materials, direct labor, and variable manufacturing overhead—in unit product costs.

Super-Variable Costing

A costing method that classifies all direct labor and manufacturing overhead costs as fixed period costs and only direct materials as a variable product cost.