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What is the charge of Cr in the complex : [Cr(SO4)2(C2O4)2]-5?a. +5 b. +2 c. +3 d. +1 e. -3

Calculate Eocell for the following balanced redox reaction in acidic solution: 3 SO-24 + 2Cr(s) + 12 H+ → 3 SO2 (g) + 2Cr+3 + 6 H2O (acidic)  a. +1.945 V b. -0.585 V c. +0.585 V d. -0.895 V e. +0.895 V

Classify NaOH as a strong base, weak base, strong acid, or weak acid. Then answer the following question. What is the pH of a 7.8 x 10-5 M NaOH(aq) solution? a. 4.1 b. 9.5 c. 9.9 d. 4.5 e. 13.0

Consider the following data for the reaction: A + B → products [A] [B] Rate 0.2 M 0.1 M 20 M/s 0.4 0.1 80 0.4 0.2 320 What is the rate law? (Suggestion: first determine the order in both A and B by the ratio technique.) a. Rate = k[A]2 b. Rate = k[A][B] c. Rate = k[A][B]2 d. Rate = k[A]2 [B]2 e. Rate = k[A]2 [B]   Tables.pdf Periodic Table with New Elements.pdf

What is the Ka expression for HClO2?   a.

What [Ag+] is needed to begin precipitating Ag2SO4 (s) from a 0.092 M SO4-2 solution? Ksp of Ag2SO4 = 1.6 x 10-5 a. 1.3 x 10-2 M b. 1.2 x 10-3 M c. 8.7 x 10-5 M d. 1.7 x 10-4 M e. 6.6 x 10-3 M

Suppose a solution contains 0.7 M Ba2+ (aq) and 0.4 M Mg2+ (aq). Fluoride ions, F- , are then slowly added to the solution.  At what [F-] will MgF2 (s) start to precipitate? (Suggestion: Write the dissolving equation and Ksp expression for MgF2 before starting this problem.) a. 1.3 x 10-5 M b. 1.8 x 10-10 M c. 1.0 x 10-5 M d. 6.6 x 10-6 M e. 1.9 x 10-5 M   Tables.pdf Periodic Table with New Elements.pdf

Consider the following data for the reaction: A → product [A] Initial Rate 0.03 M 4.69 x 10-5 M/s  0.17 2.66 x 10-4 0.46 7.19 x 10-4 0.73  1.14 x 10-3 What is the rate law? (Hint: use the “ratio technique”) a. Rate = k[A] b. Rate = k/[A] c. Rate = k d. Rate = k/[A]2 e. Rate = k[A]2

The isotope 4921 Sc decays to 4922Ti. What decay process has occurred?  a.

What is the main reason why increasing the temperature increases the rate of a chemical reaction? A. Increasing the temperature raises the energy of activation (Ea) B. Increasing the temperature lowers the energy of activation (Ea) C. Increasing the temperature increases the number of molecules that have the correct orientation for reacting D. Increasing the temperature increases the concentration of reactant molecules E. Increasing the temperature increases the number of molecules that have enough energy to react.     Tables.pdf Periodic Table with New Elements.pdf