Question

a 25.0 ml portion of a 6.00 m nacl solution is used to make 1.00 l of a new solution. what is the concentration of the new solution? (hint: make sure both volume units are the same) \bigcirc 150 m \bigcirc 240 m \bigcirc 0.150 m \bigcirc 2.40 m

Explanation:

Step1: Recall dilution formula

The dilution formula is \( M_1V_1 = M_2V_2 \), where \( M_1 \) is initial molarity, \( V_1 \) is initial volume, \( M_2 \) is final molarity, \( V_2 \) is final volume.

Step2: Convert volume units

Initial volume \( V_1 = 25.0 \, \text{mL} = 0.0250 \, \text{L} \) (since \( 1 \, \text{L} = 1000 \, \text{mL} \)).

Step3: Plug values into formula

Given \( M_1 = 6.00 \, \text{M} \), \( V_1 = 0.0250 \, \text{L} \), \( V_2 = 1.00 \, \text{L} \).
From \( M_1V_1 = M_2V_2 \), solve for \( M_2 \):
\( M_2=\frac{M_1V_1}{V_2}=\frac{6.00 \, \text{M} \times 0.0250 \, \text{L}}{1.00 \, \text{L}} \)

Step4: Calculate \( M_2 \)

\( M_2=\frac{0.150 \, \text{mol}}{1.00 \, \text{L}} = 0.150 \, \text{M} \) (since \( M_1V_1 \) gives moles, and dividing by \( V_2 \) gives molarity).

Answer:

0.150 M