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In: Chemistry

A buffer is prepared by adding 150 mL of 1.0 M NaOH to 250 mL of...

A buffer is prepared by adding 150 mL of 1.0 M NaOH to 250 mL of 1.0 M NaH2PO4. How many moles of HCl must be added to this buffer solution to change the pH by 0.25 units? Assume the total volume remains unchanged at 400 mL.
For H2PO4-, Ka = 6.3 × 10-8.

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