A precipitate will form if the resulting compound is insoluble in water. For example, a silver nitrate solution (AgNO₃) is mixed with a solution of magnesium bromide (MgBr₂). The balanced reaction would be: ... Therefore, AgBr will precipitate out.

Which will form a precipitate first?

In solutions with equal concentrations of target ions, the ion forming the least soluble compound will precipitate first (at the lowest concentration of counter ion), with the other ions subsequently precipitating as their compound's solubilities are reached.

Is agcl2 a precipitate?

If two solutions are mixed together it is possible that two ions could combine to form an insoluble ionic complex. ... Since Ag⁺ is now in solution with Cl^- the two will combine to form AgCl, and the AgCl will precipitate from solution.