This preview shows pages 1–3. Sign up to view the full content.
This preview has intentionally blurred sections. Sign up to view the full version.
View Full Document
Unformatted text preview: toupal (rgt374) Homework 10 Sutcliffe (52410) 1 This printout should have 20 questions. Multiplechoice questions may continue on the next column or page find all choices before answering. 001 10.0 points 4 . 78 g of Ag 2 SO 4 will dissolve in 1 L of water. Calculate the solubility product constant for this salt. Correct answer: 1 . 44159 10 5 . Explanation: solubility of Ag 2 SO 4 = 4 . 78 g / 1 L H 2 O solubility = parenleftbigg 4 . 78 g Ag 2 SO 4 L parenrightbigg parenleftbigg 1 mol Ag 2 SO 4 311 . 77 g Ag 2 SO 4 parenrightbigg = 0 . 0153318 mol / L Ag 2 SO 4 Ag 2 SO 4 (s) 2 Ag + (aq) + SO 2 4 (aq) [Ag + ] = 2 (0 . 0153318) = 0 . 0306636 [SO 2 4 ] = 0 . 0153318 K sp = [Ag + ] 2 [SO 2 4 ] = (0 . 0306636) 2 (0 . 0153318) = 1 . 44159 10 5 002 10.0 points A saturated solution of MgF 2 (s) is found to have a Mg 2+ concentration of 2 . 10 3 M. What is the value of K sp for MgF 2 ? 1. 8 . 10 9 2. 3 . 2 10 8 correct 3. 4 . 10 12 4. 1 . 10 9 5. 4 . 10 9 Explanation: [Mg 2+ ] = 2.0 10 3 M MgF 2 Mg 2+ + 2 F K sp = [Mg 2+ ] [F ] 2 = ( x ) (2 x ) 2 = 4 x 3 = 4 ( 2 10 3 ) 3 = 3 . 2 10 8 003 10.0 points A solution of AgI contains 2 . 2 mol/L Ag + . K sp of AgI is 8 . 3 10 17 . What is the max imum I concentration that can exist in this solution? Correct answer: 3 . 77273 10 17 mol / L. Explanation: [Ag + ] = 2 . 2 [I ] = ? K sp = 8 . 3 10 17 AgI(s) Ag + (aq) + I (aq) K sp = [Ag + ] [I ] [I ] = K sp [Ag + ] = 8 . 3 10 17 2 . 2 = 3 . 77273 10 17 mol / L 004 (part 1 of 2) 10.0 points It is necessary to add iodide ions to precipitate the lead(II) ions from 250 mL of 0 . 041 M Pb(NO 3 ) 2 (aq). What minimum iodide ion concentration is required for the onset of PbI 2 precipitation? The solubility product of PbI 2 is 1 . 4 10 8 . Correct answer: 0 . 000584349 mol / L. Explanation: [Pb 2+ ] = 0 . 041 M K sp = 1 . 4 10 8 The balanced equation is Pb 2+ (aq) + 2 I (aq) PbI 2 (s) Analyzing the reaction using concentrations, Pb 2+ + 2 I PbI 2 . 041 + x . 041 x toupal (rgt374) Homework 10 Sutcliffe (52410) 2 K sp = [Pb 2+ ] [I ] 2 1 . 4 10 8 = (0 . 041) ( x ) 2 x = 0 . 000584349 mol / L = [I ] 005 (part 2 of 2) 10.0 points What mass of KI must be added for PbI 2 to form?...
View
Full
Document
 Spring '09
 Sutcliffe
 Chemistry

Click to edit the document details