A chemist adds 260.0 mL of a \( 3.4 M \) potassium iodide \( (\mathrm{KI}) \) solution to a reaction flask. Calculate the millimoles of potassium iodide the chemist has added to the flask. Round your answer to 2 significant digits. \( \square_{\mathrm{mmol}} \)

To find the millimoles of potassium iodide (KI) added to the flask, we can use the formula: Millimoles (mmol) = Molarity (M) × Volume (L) × 1000. First, convert the volume from mL to L: 260.0 mL = 0.260 L. Now calculate: Millimoles = 3.4 M × 0.260 L × 1000 = 884.0 mmol. Rounding this to two significant digits gives us \( \mathbf{88 \, \text{mmol}} \).