A Solution Is Prepared by Dissolving 20

question 48

Multiple Choice

A solution is prepared by dissolving 20.0 g of K₂HPO₄ and 25.0 g of KH₂PO₄ in enough water to produce 1.0 L of solution. What is the pH of this buffer? For phosphoric acid (H₃PO₄) , K_a2 = 6.2 × 10^-8.

• A) 7.70
• B) 7.42
• C) 7.21
• D) 7.00
• E) 6.72

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Definitions:

Vascular System

The complex network of blood vessels that circulate blood throughout the body, including arteries, veins, and capillaries.

Capillaries

The smallest blood vessels in the body, which facilitate the exchange of oxygen, carbon dioxide, and other nutrients and wastes between the blood and tissues.

Blood

The circulatory fluid that supplies oxygen and nutrients to the cells and carries away carbon dioxide and other waste products.

Cardiorespiratory Fitness

A measure of the efficiency of the heart, lungs, and vascular system in delivering oxygen to the body during sustained physical activity.