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Write the correct dissolving equation for Au(OH)3 (s) on scratch paper, and then answer the following question. Will a ppt of Au(OH)3 (s) form if you mix 2.8 x 10-12 M Au3+ (aq) with 5.6 x 10-10 M OH- (aq)? Which of the following is entirely correct?   a.  Q= 4.9 x 10-40, ppt forms b.  Q= 4.9 x 10-40,  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 

Classify H2CO3 as a strong base, weak base, strong acid, or weak acid, and then answer the followingquestion. What is the pH ofa 0.321 M H2CO3 (aq) solution? a. 6.9 b. 8.6 c. 5.4 d. 10.6 e. 3.4

A solution contains 0.00396 M SO42- (aq) and 0.00998 M CO32- (aq). If Ag+ (aq) ions are slowly added, which compound (Ag2SO4 or Ag2CO3) will ppt first and at what [Ag+]? (In other words, which of the following is entirely correct?) (Suggestion: Write the dissolving equations and Ksp expressions for Ag2SO4  and Ag2CO3 before starting this problem.) a. Ag2SO4 precipitates first at [Ag+] = 6.4 x 10-2 M b. Ag2CO3 precipitates first at [Ag+] = 2.9 x 10-5 M c. Ag2CO3 precipitates first at [Ag+] = 8.2 x 10-10 M d. Ag2SO4 precipitates first at [Ag+] = 4.0 x 10-3 M e. Ag2CO3 precipitates first at [Ag+] = 1.3 x 10-5 M   Tables.pdf Periodic Table with New Elements.pdf  

If ÄH and ÄS are both negative for a reaction, then the reaction is: a. nonspontaneous at low temperatures and spontaneous at high temperatures. b. spontaneous at low temperatures and nonspontaneous at high temperatures. c. spontaneous at all temperatures. d. nonspontaneous at all temperatures.   e. none of the choices given above

A radioactive isotope has a half-life,  t½ = 27.3 yr.How long will it take for a 3.27 mCi sample of this isotope to decay to 0.351 mCi? a. 0.0817 yr b. 38.2 yr c. 133 yr d. 87.9 yr e. 60.9 yr

What is [H+] when pOH = 8.3?   a. 2.0 x 10-6 M b. 5.0 x 10-9 M c. 3.3 x 10-3 M d. 5.7 M e. 5.0 x 105 M

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