of its original concentration, the separation is considered effective. 3. Step-by-Step Problem Solving Strategy To excel at the POGIL activity, follow these steps: Look up the Kspcap K sub s p end-sub values for all potential precipitates. Determine the required concentration: Calculate the needed for each ion to start precipitating ( Order the ions: The ion requiring the lowest precipitates first. Calculate remaining concentration: Use the
Ksp = [Ag⁺][Cl⁻] = 1.8 × 10⁻¹⁰ [Cl⁻] = (1.8×10⁻¹⁰) / (0.01) = 1.8 × 10⁻⁸ M
formed, the fractional precipitation separation is highly effective and virtually complete. Key Takeaways for Your POGIL Review fractional precipitation pogil answer key
Fractional precipitation occurs when a reagent is added dropped-by-drop to a solution containing multiple dissolved ions. If the reagent can form an insoluble precipitate with more than one of these ions, the ions will not drop out of the solution at the same time. Instead, the compound with the lower solubility will precipitate first. Key Terms to Know
A typical POGIL problem will provide a solution containing two ions—for example, . You are asked what happens when silver nitrate ( AgNO3AgNO sub 3 ) is slowly added. of its original concentration, the separation is considered
Understanding Fractional Precipitation: A Guide to the POGIL Activity
Ksp=[Ag+][I−]cap K sub s p end-sub equals open bracket Ag raised to the positive power close bracket open bracket I raised to the negative power close bracket If the reagent can form an insoluble precipitate
to find the exact point where the solution becomes saturated. For Silver Iodide ( AgIcap A g cap I
% Remaining=([I−]remaining[I−]initial)×100% Remaining equals open paren the fraction with numerator open bracket cap I raised to the negative power close bracket sub r e m a i n i n g end-sub and denominator open bracket cap I raised to the negative power close bracket sub i n i t i a l end-sub end-fraction close paren cross 100