Question

ADVANCED MATERIAL Calculating the solubility of an lonic compound when a common ion is present Calculate the solubility at 25 °C of CaF, in pure water and in a 0.0030 M NaF solution. You'll find K., data in the ALEKS Data tab. Round both of your answers to 2 significant digits. solubility in pure water: solubility in 0.0030 M NaF solution: 0 x 5 ?
Ksp = 3.45 • 10^-11

Answer 1

Cafall the Cat (aq) + 2F (ag Kep 23.45 X10" of s' is solubility in molsh, then. kop. [cat] [F-7² - (S) (25) - 453 433 2 3.45X104 So 2.0518104 molle Allow solubility in pure water - 12.05x10 mol/L Molas mass of cafe - 78.07 g/mol Solubility in gli - 2.05 410" x 78-07 g/L - 11.6*102 g/L - Answert on 0.0030 M Naf solution, [F] = 0.0030 M. Total [F-J. (. 0030 +625) moll Ksp = (3) (0.0030 +25² Assuming is to be very small, 0.0030 +25 20.0030 kop » ($) (0.00 30) 3.45X10" = (3x106)s S = 3.83x10-6 molle angle, solubility a/3.0x104 g 2 . Answers

In pure water, solubility = 1.6 x 10^-2 g/L

In presence of 0.0030 M NaF, solubility = 3.0 x 10^-4 g/L