A Solution Is Prepared by Dissolving 0 $K _ { a }$

question 139

Multiple Choice

A solution is prepared by dissolving 0.23 mol of formic acid and 0.27 mol of sodium formate in water sufficient to yield 1.00 L of solution.The addition of 0.05 mol of HCl to this buffer solution causes the pH to drop slightly.The pH does not decrease drastically because the HCl reacts with the ________ present in the buffer solution.The $K _ { a }$ of formic acid is 1.36 × 10^-3.

• A) H₂O
• B) \( \mathrm{H}_{3} \mathrm{O}^{+} \)
• C)formate ion
• D)formic acid
• E)This is a buffer solution: the pH does not change at all upon addition of acid or base.

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Definitions:

ICD-9-PCS

International Classification of Diseases, Ninth Revision, Procedure Coding System; a coding system used to classify procedures for billing and statistical purposes in healthcare.

ICD-10-PCS

The International Classification of Diseases, Tenth Revision, Procedure Coding System; a coding system for documenting procedures in healthcare settings.

First Character

The initial symbol or letter in a sequence or string of characters, often significant in programming and data processing.

ICD-9-CM

The International Classification of Diseases, Ninth Revision, Clinical Modification; a system used in the United States for coding and classifying mortality and morbidity data until its replacement by ICD-10-CM.