What Is the PH of a Buffered System Made by Dissolving

question 85

Multiple Choice

What is the pH of a buffered system made by dissolving 17.42 g of KH₂PO₄ and 20.41 g of K₂HPO₄ in water to give a volume of 200.0 mL? The K_a2 for dihydrogen phosphate is 6.2 × 10^-8 and the equilibrium reaction of interest is H₂PO₄^-(aq) + H₂O(l) ⇌ H₃O⁺(aq) + HPO₄^-(aq) .

• A)7.03
• B)7.17
• C)7.38
• D)7.58

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Across The Line

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Full Voltage

A term typically referring to the application of full line voltage to a device, ensuring it operates at its intended performance level.

Electrical Supply

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