How many millimoles (mmol) of KOH are present in 33.4 mL of 0.500 M KOH solution?

• A. 16.7 mmol
• B. 8.35 mmol
• C. 0.167 mmol
• D. 1.67 mmol

Answer: (B)

Verified step by step guidance

1. Identify the given information: volume of KOH solution = 33.4 mL, molarity (M) of KOH = 0.500 M.
2. Convert the volume from milliliters to liters because molarity is expressed in moles per liter. Use the conversion: \(\text{Volume (L)} = \frac{\text{Volume (mL)}}{1000}\).
3. Use the molarity definition to find moles of KOH: \(\text{Moles of KOH} = \text{Molarity} \times \text{Volume (L)}\).
4. Convert moles of KOH to millimoles by multiplying by 1000, since 1 mole = 1000 millimoles: \(\text{Millimoles} = \text{Moles} \times 1000\).
5. Combine all steps into one expression to calculate millimoles of KOH: \(\text{Millimoles} = 0.500 \times \frac{33.4}{1000} \times 1000\).