Fractional - Precipitation Pogil Answer Key 2021

A solution contains 0.020 M chloride ions (Cl⁻) and 0.020 M iodide ions (I⁻). Silver nitrate (AgNO₃) is slowly added. Ksp(AgCl) = 1.8 × 10⁻¹⁰, Ksp(AgI) = 8.5 × 10⁻¹⁷. Which precipitate will form first?

Can the two ions be effectively separated? Explain. fractional precipitation pogil answer key 2021

That’s the hidden gem. The POGIL forces you to calculate the [X⁻] needed to start precipitation for each ion. If those two concentrations are far apart (say, 10⁻⁵ M vs 10⁻¹ M), you can easily stop addition in between. If they’re close (10⁻⁵ M vs 10⁻⁴ M), you’ll precipitate both at nearly the same time—no separation possible. A solution contains 0