Answer:
1.36 × 10³ mL of water.
Explanation:
We can utilize the dilution equation. Recall that:
[tex]\displaystyle M_1V_1= M_2V_2[/tex]
Where M represents molarity and V represents volume.
Let the initial concentration and unknown volume be M₁ and V₁, respectively. Let the final concentration and required volume be M₂ and V₂, respectively. Solve for V₁:
[tex]\displaystyle \begin{aligned} (2.50\text{ M})V_1 &= (0.800\text{ M})(2.00\text{ L}) \\ \\ V_1 & = 0.640\text{ L} \end{aligned}[/tex]
Therefore, we can begin with 0.640 L of the 2.50 M solution and add enough distilled water to dilute the solution to 2.00 L. The required amount of water is thus:
[tex]\displaystyle 2.00\text{ L} - 0.640\text{ L} = 1.36\text{ L}[/tex]
Convert this value to mL:
[tex]\displaystyle 1.36\text{ L} \cdot \frac{1000\text{ mL}}{1\text{ L}} = 1.36\times 10^3\text{ mL}[/tex]
Therefore, about 1.36 × 10³ mL of water need to be added to the 2.50 M solution.
