Showing all calculations and specific references to the equipment needed, describe how to prepare 500mL 0.250mol/L potassium iodide(KI) solution.

Answer 1

You want how many mols? That's M x L = mols KI.
How many grams is that? That's mols = grams/molar mass. You have molar mass and mols, calculate grams.

Place that many grams KI in a 500 mL volumetric flask, add a little DI water, swirl until all KI is dissolved, add DI water to the mark on the flask, mix thoroughly, stopper.