Phosphoric Acid Is a Triprotic Acid, Ionizing in the Following $\leftrightarrows$

question 132

Multiple Choice

Phosphoric acid is a triprotic acid, ionizing in the following sequential steps:
H₃PO₄ + H₂O $\leftrightarrows$ H₂PO₄^- + H₃O⁺ $K _ { a _ { 1 } }$
H₂PO₄^- + H₂O $\leftrightarrows$ HPO₄^2- + H₃O⁺ $K _ { a_{2} }$

HPO₄^2- + H₂O $\leftrightarrows$ PO₄^3- + H₃O⁺ $K _ { a _ { 1 } }$
Which equilibrium is most important in determining the pH of a solution of sodium phosphate?

• A) HPO₄^2- + H₂O \(\leftrightarrows\)PO₄^3- + H₃O⁺
• B) H₃PO₄ + H₂O \(\leftrightarrows\)H₂PO₄^- + H₃O⁺
• C) PO₄^3- + H₂O \(\leftrightarrows\)HPO₄^2- + OH^-
• D) H₂PO₄^- + H₂O \(\leftrightarrows\)H₃PO₄ + OH^-
• E) 2H₂O \(\leftrightarrows\)H₃O⁺ + OH^-

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Definitions:

Correlation

An indicator that measures the degree to which multiple variables vary in unison.

Denseness

A measure of the compactness or crowding of objects within a given area or volume.

Slope

The measure of the steepness or inclination of a line, often describing the rate of change between two variables.

Simple Linear Regression

A statistical method that allows us to summarize and study relationships between two continuous (quantitative) variables.