A Buffer May Be Prepared by Mixing a Weak Acid

question 20

Multiple Choice

A buffer may be prepared by mixing a weak acid with a roughly equivalent amount of strong base.Which of the acids below is best for the preparation of a buffer with a pH of 9.00?

• A) chlorous acid,HClO₂;K_a = 2.8 × 10−⁸
• B) formic acid,HCO₂H;K_a = 1.9 × 10−⁴
• C) benzoic acid,HC₇H₅O₂;K_a = 6.6 × 10−⁵
• D) dihydrogen phosphate ion,H₂PO₄−;K_a = 6.2 × 10−⁸
• E) ammonium ion,NH₄⁺;K_a = 5.6 × 10−¹⁰

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Definitions:

Time-Driven Activity-Based Costing

A refinement of activity-based costing that uses time as the main cost driver to allocate costs to products or services.

Order Fulfillment Department

The division within a company responsible for processing and delivering orders to customers.

Capacity Analysis

entails assessing the maximum output level an organization can achieve with its current resources, considering constraints like space and machinery.

Time-Driven Activity-Based Costing

A refinement of activity-based costing that assigns costs based on the duration activities require, leveraging time as the primary driver.