Problem- A 25.0-mL solution of 0.0700 M EDTA was added to a 31.0-mL sample containing an unknown concentration of V3. All V3 present formed a complex, leaving excess EDTA in solution. This solution was back-titrated with a 0.0450 M Ga3 solution until all the EDTA reacted, requiring 13.0 mL of the Ga3 solution. What was the original concentration of the V3 solution?
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