Final answer:
The volume of 250 millimoles of liquid octane (C8H18) is found by multiplying the number of millimoles by the molar volume, resulting in 20.6 L.
Step-by-step explanation:
The question asks to calculate the volume of 250 millimoles of liquid octane (C8H18) given the molar volume is 82.4 mL/mol. To find the volume of 250 millimoles of octane, we use the formula:
Volume = (Number of millimoles) x (Molar volume)
Volume = 250 mmol x 82.4 mL/mol
Volume = 20,600 mmol·mL/mol
Since 1 mmol·mL/mol equals 1 mL, the volume is 20,600 mL which can also be expressed as 20.6 L. Therefore, the volume of 250 millimoles of C8H18 is 20.6 L.