Answer:
sodium fluoride
Explanation:
When we add sodium fluoride to a solution of a given mixture, we get barium fluoride from Ba, which would be an insoluble salt, and silver fluoride from Ag, which would be a soluble salt.
The solubility rule will be used to determine the barium salt that forms as a precipitate and leaves Ag+ salt in the solution.
From the following equations, we will see that the precipitate is formed in Ba but Ag remains dissolved in the solution.


Not necessary. That is because the states could differ, as if one is a solid, the particles are squished together, and if its a liquid, the particles are farther apart.
Milliliters is the metric unit for a graduated cylinder