Step 1
A dilution is calculated as:
[tex]\begin{gathered} M1\text{ x V1 = M2 x V2 \lparen1\rparen} \\ M1\text{ = concentration 1; M2 = concentration 2} \\ V1\text{ = volume 1; V2 = volume 2} \end{gathered}[/tex]----------------------
Step 2
Information provided of lithium acetate:
M1 = 2.6 M
V1 = 350 mL
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M2 = unknown
V2 = 800 mL
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Step 3
Procedure: from (1)
M1 x V1/V2 = M2
2.6 M x 350 mL/800 mL = M2
1.1 M approx. = M2
Answer: M2 = 1.1 M