How many moles of hydrochloric acid (HCl) are present in 500. mL of a 0.300 M solution?

• A. 0.600 mol
• B. 0.150 mol
• C. 0.050 mol
• D. 0.300 mol

Answer: (B)

Verified step by step guidance

1. Identify the given information: volume of the solution is 500. mL and the molarity (M) of HCl is 0.300 M.
2. Convert the volume from milliliters to liters because molarity is expressed in moles per liter. Use the conversion: \$1\, \text{L} = 1000\, \text{mL}\(, so \)V = \frac{500.\, \text{mL}}{1000} = 0.500\, \text{L}$.
3. Recall the definition of molarity: \(M = \frac{\text{moles of solute}}{\text{liters of solution}}\).
4. Rearrange the molarity formula to solve for moles of solute: \(\text{moles of HCl} = M \times V\).
5. Substitute the known values into the equation: \(\text{moles of HCl} = 0.300\, \text{mol/L} \times 0.500\, \text{L}\) to find the number of moles.