What is the molarity of a solution prepared by diluting 20.0mL of 25.0 M HCI solution with 10.0 mL of water

1. Calculate the final volume:
V_2 = 20.0 \, \text{mL} + 10.0 \, \text{mL} = 30.0 \, \text{mL}

2. Use the dilution formula to find the final molarity:
M_2 = \frac{M_1 \times V_1}{V_2}
M_1 = 25.0 \, \text{M}
V_1 = 20.0 \, \text{mL}
V_2 = 30.0 \, \text{mL}

3. Plug in the values:
M_2 = \frac{25.0 \, \text{M} \times 20.0 \, \text{mL}}{30.0 \, \text{mL}} = 16.7 \, \text{M}

Answer: 16.7 \, \text{M}