What Ratio of [NH₄⁺]/[NH₃] Would Provide a Buffer of PH

question 45

Multiple Choice

What ratio of [NH₄⁺]/[NH₃] would provide a buffer of pH low enough to avoid precipitation of Co(OH) ₂(s) from a 0.50 M Co²⁺(aq) solution? (K_b for NH₃ = 1.8 × 10^-5 and K_{sp for} Co(OH) ₂= 2.0 × 10^-14

• A)1/50
• B)1/90
• C)1/1
• D)90/1
• E)50/1

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Overhead Allocation Base

A measure or standard used to distribute indirect costs to various cost objects, such as products or departments, typically involving labor hours, machine hours, or cost centers.

Departmental Overhead Rate

A rate used to allocate overhead costs to specific departments, based on criteria such as department size or usage of overhead resources.

Machine Hours

A measure of the total operating time of machinery within a certain period.

Departmental Overhead Rates

The allocation of indirect costs to specific departments based on their respective shares of direct costs or activity drivers.