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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

A solution contains 0.414 M NH4Cl(aq). What concentration of NH3 (aq) must be added to make abuffer of pH 9.55? a. 0.207 M b. 0.826 M c. 0.124 M d. 0.559 M e. 4.82 M

For the reaction: A → products Suppose a chemist makes the following three graphs from data he obtains in the lab: What is the rate law? (Hint: first determine the order of the reaction by looking at the shapes of the graphs.) a. Rate = k[A]3 b. Rate = k[A]2 c. Rate = k[A] d. Rate = k   Tables.pdf Periodic Table with New Elements.pdf

Write the correct dissolving equation for Al(OH)3 (s) on scratch paper, and then answer the following question. What is the correct Ksp expression for the dissolving of Al(OH)3 (s)?   a.  Ksp = [Al3+] [OH-]3 b.  Ksp = [Al3+] [O2-]3[H+]3 c. Ksp = [Al3+]3 [OH-] d. Ksp = [Al3+] [OH-] e. Ksp = [Al3+] 3[OH-]

Suppose 125 mL of 0.20 M Mg2+ (aq) is mixed with 575 mL of 9.3 x 10-3 M F- (aq). Calculate Q and determine whether a ppt of MgF2 (s) will form. (In other words, which of the following is entirely correct?  (Suggestion: Write the dissolving equation and Ksp expression for MgF2 before starting this problem.) a. Q = 2.7 x 10-4 ppt forms b. Q = 1.7 x 10-5 ppt forms c. Q = 1.9 x 10-3 ppt forms d. Q = 4.0 x 10-13 no ppt e. Q = 2.1 x 10-6 ppt forms   Tables.pdf Periodic Table with New Elements.pdf

Which is the correct equation for 12956Ba decaying by electron capture?  a. 56129Ba  →  55129Cs +  +1 0e b. 56129Ba + -1 0e →  57 129La c. 56129Ba + -1 0e → 55129Cs d. 56129Ba → 57 129La + -1 0e e. 56129Ba → 54 125Xe + 2 4He

The Ksp of Ag2C2O4 is 3.5 x 10-11 . What is the solubility of Ag2C2O4(s) in moles per liter (mol/L) pure water? (Note: The molar mass of Ag2C2O4 is not needed in this problem, which asks for molesper L.) a. 4.2 x 10-6 mol/L b. 3.3 x 10-4 mol/L c. 2.1 x 10-4 mol/L d. 5.9 x 10-6 mol/L  e. 8.8 x 10-12 mol/L 

The Ksp of bismuth iodide, BiI3 [Molar Mass = 589.68], is 8.1 x 10-19. If BiI3 (s) is dissolved in pure water, what is the solubility in grams per liter (g/L)? (Suggestion: Write the dissolving equation and Ksp expression for BiI3 before starting this problem.) a. 3.1 x 10-7 g/L b. 7.8 x 10-3 g/L c. 1.0 x 10-2 g/L d. 1.3 x 10-2 g/L e. 1.8 x 10-2 g/L   Tables.pdf Periodic Table with New Elements.pdf

What [PO43-] is required to just begin precipitation of Zn3(PO4)2 (s) from a solution of 0.2 M Zn2+ (aq)? (Suggestion: Write the dissolving equation and Ksp expression for Zn3(PO4)2 before starting this problem.) a. 1.1 x 10 -30 M b. 2.1 x 10 -16 M c. 1.1 x 10 -15 M d. 5.3 x 10 -16 M e. 1.0 x 10 -16 M   Tables.pdf Periodic Table with New Elements.pdf