How does one prepare a 0.1M standard solution of potassium hydrogen phthalate?

To prepare a 0.1M standard solution of potassium hydrogen phthalate, you would first weigh out the appropriate amount of potassium hydrogen phthalate (KHPh) based on its molar mass, which is 204.22 g/mol. Dissolve this amount in distilled water and make up the solution to the desired volume, typically in a 1 liter volumetric flask. Finally, mix the solution thoroughly to ensure complete dissolution.