Unformatted text preview: 8 SCORING GUIDELINES (Form B)
Question 3 (continued)
(e) Circle the diagram below that best represents the results after the mixture reacts as completely as possible. Explain the reasoning used in making your choice. The rightmost diagram in the top row should be circled. PbI2 precipitates and Pb(NO3)2 is the limiting reactant, so there is essentially no Pb2+ in solution. Because there was so much NaI in excess, some of the I− remains in solution, along with the Na+ and NO3−. One point is earned for the selection of the correct diagram. One point is earned for the correct rationale. © 2008 The College Board. All rights reserved. Visit the College Board on the Web: www.collegeboard.com. AP® CHEMISTRY 2008 SCORING GUIDELINES (Form B)
For each of the following three reactions, in part (i) write a balanced equation for the reaction and in part (ii) answer the question about the reaction. In part (i), coefficients should be in terms of lowest whole numbers. Assume that solutions are aqueous unless otherwise...
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