To determine the concentration of solution A and the type of reaction between A and water.

The problem asks to determine the concentration of solution A and the type of reaction between A and water.

Part 1: Determine the concentration of solution A using solution B.

Based on the provided information:

• Solid A is potassium dichromate ($\text{K}_2\text{Cr}_2\text{O}_7$).
• Solution A is prepared from solid A, so solution A contains $\text{Cr}_2\text{O}_7^{2-}$ ions.
• The titration procedure states that solution A is in the burette and is used to titrate the contents of the conical flask.
• The conical flask contains 25 cm³