Question

Calculate Q to determine whether or not a precipitate will form in a solution containing 0.043 M Ca(NO3)2 and 0.0055 M NaF. Step 1: identify the possible precipitate. In this example, it is CaF2. Look up its Ksp value (table 16.2). Step 2: Write a balanced equation for dissolution of CaF2: Step 3: Write the equation for Ksp for CaF2: Step 4: Write an expression for Q: Step 5: Plug in the concentrations above to calculate Q: Step 6: Compare the value of Q to the value of Ksp. What will happen?

Answer 1

Answer: Q = 1029x156 , Cafe with precipitate Explanation concentration of Naf - 0.0055 M concentration of CaNO3) = 00043 M step-12 sref possible precipitate is cafe COLNO) + 2NaF cafel + 2 NaNO3 Ksp value of CaF2 = 3092101 (standard value) Step-2 & Balanced equation for caFa dissolution when ionic salt (CAF) dissolves in water, it dissociates into separate hydrated ions initially. - At equilibrium - Cata(s) - Camilaa) + 2 Flaa) Step-3: 'the solubility product is ksp. It is found from the balanced equation the exponent on each onent is based on the number of moles .: Ksp = [ca2+] [F]? Ksp valid for 'Saturated Solutions"

Step 4: Ion product is the product of concentration of ions of salt each raised to the power of their coefficients in the balanced equation in solution "aut any concentration Step-s from the given data concentration et pe 0.0055 M concentration of co2t = 0.043 m " Ion product Q= [ca2+] [F]? : Q = 0.043 x(0.0055)? Q = 43x173 x 3.0x105 Q = 129x108 Q = 1.29x106 hence pr upitation takes place