A) What mass of Potassium Hydrogen Phthalate (KHP) will just neutralize 21 mL of 0.20 M NaOH?

You get A.

KHC8H5O4 + NaOH -> NaKC8H5O4 + H2O

All one to one, so find moles NaOH

Molarity = moles of solute/liters of solution

0.20 M NaOH = moles NaOH/0.021 liters

= 0.0042 moles NaOH
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0.0042 moles NaOH (1 mole KHP/1 mole NaOH)(205.228 grams/1 mole KHP)

= 0.86 grams KHP
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