Final answer:
To achieve a concentration of 0.100 M, an 87.0 mL aliquot of the 0.500 M stock solution should be diluted to a total volume of 0.86 mL.
Step-by-step explanation:
To dilute the 0.500 M stock solution to 0.100 M, an 87.0 mL aliquot of the stock solution must be diluted. The volume needed for the diluted solution can be calculated using the formula: (stock concentration) x (stock volume) = (final concentration) x (final volume). Substituting the given values, we have: (0.500 M) x (0.085 mL) = (0.100 M) x (V). Solving for V gives a volume of approximately 0.86 mL. Therefore, the 87.0 mL aliquot should be diluted to a total volume of 0.86 mL to achieve a concentration of 0.100 M.