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What is the solubility of BiI3 (s) (in g/L) in a solution that contains 0.24 M Bi3+ (aq)? a. 8.8 x 10-4 g/L b. 2.9 x 10-4 g/L c. 6.6 x 10-16 g/L d. 5.0 x 10-7 g/L e. 2.0 x 10-15 g/L   Tables.pdf Periodic Table with New Elements.pdf

A buffer is prepared by dissolving HF and NaF in water.  Which of the following is the net ionic equation describing how the buffer neutralizes an acid (H+ ) that is added to the buffer?  a. H+ + OH- → H2Ob. H+ + NaF → Na+ + HF  c. H+ + HF → H2F+d. H+ + H2O → H3O+e. H+ + F- → HF

What pH is required to just begin precipitating Ca(OH)2 (s) from a solution containing 0.005 M Ca2+(aq)? (Suggestion: Write the dissolving equation and Ksp expression for Ca(OH)2 before starting this problem.) a. 10.4 b. 1.8 c. 3.6 d. 12.2 e. 11.7   Tables.pdf Periodic Table with New Elements.pdf

Look up the Ka value of each acid below in your CHM-132 Tables, and then answer the following question. Which of the following is the strongest acid?   a. NH4+ b. HCHO2 c. HC2H3O2 d. HClO e. HCN

For a chemical reaction at a given temperature, which one of the following statements about Q and Keq istrue? a. If Q > Keq , the reaction will shift to the right to reach equilibrium.b. The reaction can have only one Q value.c. Keq is calculated by plugging in initial pressures or concentrations.d. Q and Keq cannot be equal.e. The reaction can have only one Keq value.

4 PH3 (g) ➝ P4(s) + 6 H2 (g) The reaction is first order in PH3 (g) and has a rate constant k of 6.28 x 10-2 s-1 . What is the half-life, t½? a. 15.9 s b. 4.35 x 10-2 s c. 9.06 x 10-2 s d. 35.0 s e. 11.0 s   Tables.pdf Periodic Table with New Elements.pdf

What is the % ionization of 0.08 M HC2H3O2 (aq) from the previous problem?   a. 0.0225 % b. 0.0150 % c. 0.00180 % d. 1.50 % e. 0.00837 %

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 BaF2 (s) start to precipitate? (Suggestion: Write the dissolving equation and Ksp expression for BaF2 before starting this problem.) a. 2.6 x 10-7 M b. 6.7 x 10-4 M c. 5.1 x 10-4 M d. 2.5 x 10-4 M e. 9.5 x 10-4 M   Tables.pdf Periodic Table with New Elements.pdf

Write the correct dissolving equation for PbSO4 (s) on scratch paper, and then answer the following question. Will a ppt of PbSO4 (s) form if you mix 1.6 x 10-2 M Pb(NO3)2 (aq) with 5.5 x 10-4 M Na2SO4 (aq)? Which of the following is entirely correct?   a.  Q= 8.8 x 10-6, ppt forms b.  Q= 8.8 x 10-6, no ppt c.  Q= 1.3 x 10-8, no ppt d.  Q = 7.7 x 10-11, ppt forms e.  Q = 7.7 x 10-11, no ppt

Suppose 20 mL of 1.5 x 10-8 M Pb(NO3)2 (aq) is mixed with 320 mL of 8.8 x 10-7 M Na2CO3 (aq). Calculate Q and determine whether a ppt of PbCO3 (s) will form. (In other words, which of the  following is entirely correct?) (Suggestion: Write the dissolving equation and Ksp expression for PbCO3 before starting this problem.) a. Q = 1.3 x 10-14 , no ppt b. Q = 1.3 x 10-14 , ppt forms c. Q = 7.3 x 10-16 , ppt forms d. Q = 7.3 x 10-16 , no ppt e. Q = 2.5 x 10-9 , ppt forms   Tables.pdf Periodic Table with New Elements.pdf