Questions: To prepare for a lab experiment, Ted is making a solution that uses two types of concentrations of HCl (hydrochloric acid): 80 mL of 50% HCl solution, and 120 mL of 20% HCl solution. What is the HCl concentration of the mixed solution? a.) 32% b.) 91% c.) 38% d.) 9%

Solution Steps

• For the 80 mL of \(50\%\) HCl solution: \[ \text{Amount of HCl} = 80 \, \text{mL} \times 0.50 = 40 \, \text{mL} \]
• For the 120 mL of \(20\%\) HCl solution: \[ \text{Amount of HCl} = 120 \, \text{mL} \times 0.20 = 24 \, \text{mL} \]

• Add the amounts of HCl from both solutions: \[ \text{Total HCl} = 40 \, \text{mL} + 24 \, \text{mL} = 64 \, \text{mL} \]

• Add the volumes of both solutions: \[ \text{Total Volume} = 80 \, \text{mL} + 120 \, \text{mL} = 200 \, \text{mL} \]

• Use the formula for concentration: \[ \text{Concentration} = \left( \frac{\text{Total HCl}}{\text{Total Volume}} \right) \times 100\% \] \[ \text{Concentration} = \left( \frac{64 \, \text{mL}}{200 \, \text{mL}} \right) \times 100\% = 32\% \]

Final Answer