A Phosphate Buffer Solution (25

question 23

Multiple Choice

A phosphate buffer solution (25.00 mL sample) used for a growth medium was titrated with 0.1000 M hydrochloric acid. The components of the buffer were sodium monohydrogen phosphate and sodium dihydrogen phosphate. The first endpoint occurred at a volume of 10.32 mL; the second occurred after an additional 18.62 mL was added, for a total volume of 28.94 mL. What was the approximate ratio of HPO₄^2- to H₂PO₄^- in the buffer?

• A) 1:1
• B) 4:5
• C) 5:3
• D) 5:4
• E) 3:5

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Definitions:

Beta

A measure of a stock's volatility in relation to the overall market; a higher beta indicates greater volatility.

Capital Asset Pricing Model

The Capital Asset Pricing Model is a formula used to determine the expected return on an investment based on its risk relative to the overall market.

Retained Earnings

Retained earnings are the portion of a company's profits that are kept or retained rather than being paid out as dividends to shareholders, used for reinvestment in the business, debt reduction, or other purposes.

Cost of Equity

The return that investors expect for investing in a company's equity, often calculated using models such as the Capital Asset Pricing Model (CAPM).