Spring 2019 CHEM 102 Dr Collins SI Leader Nikhil Manuel nsmanuel100 tamu edu https sites google com tamu edu sichemistry102 home Tuesday 6 30 7 30 ZACH 340 Wednesday 6 30 7 30 ZACH 353 Thursday 6 30 7 30 ZACH 340 SI Session EXAM 3 REVIEW 4 13 19 Chapter 14 Buffers Conceptual Review a What is necessary for a buffer solution How is this influenced by the common ion effect b Write the two variations of the Henderson Hasselbach equation c What types of indicators should you use for each titration d Write the methodology for each titration type 1 SA SB titration 2 WA SB titration 3 WB SA titration Texas A M University Academic Success Center Spring 2019 CHEM 102 Dr Collins SI Leader Nikhil Manuel nsmanuel100 tamu edu https sites google com tamu edu sichemistry102 home Tuesday 6 30 7 30 ZACH 340 Wednesday 6 30 7 30 ZACH 353 Thursday 6 30 7 30 ZACH 340 Practice Problems a Calculate the pH of 1 A buffer solution consisting of 0 50 M CH3COOH and 0 50 M CH3COONa Then calculate the pH 2 After adding 0 020 moles of solid NaOH to 1 0 L of the buffer solution in part 1 3 After adding 0 020 moles of HCl to 1 0 L of the buffer solution in part 1 b An environmental chemist needs a carbonate buffer of pH 10 00 to study the effects of the acid rain on limestone rich soils How many grams of Na 2CO3 must she add to 1 5 L of freshly prepared 0 20 M NaHCO3 to make the buffer Ka of HCO3 is 4 7 10 11 Texas A M University Academic Success Center Spring 2019 CHEM 102 Dr Collins SI Leader Nikhil Manuel nsmanuel100 tamu edu https sites google com tamu edu sichemistry102 home Tuesday 6 30 7 30 ZACH 340 Wednesday 6 30 7 30 ZACH 353 Thursday 6 30 7 30 ZACH 340 c Calculate the pH during the titration of 40 00 mL of 0 1000 M propanoic acid after adding the following volumes of 0 1000 M NaOH 1 0 00 mL 2 30 00 mL 3 40 00 mL 4 50 00 mL d Consider the titration of 100 0 mL of 0 200 M CH 3NH2 by 0 100 M HCl Calculate the pH Kb for CH3NH2 4 4 x 10 4 1 after 0 0 mL of HCl added 2 after 20 0 mL of HCl added 3 after 65 0 mL of HCl added 4 at the equivalence point 5 after 300 0 mL of HCl added 6 what volume of HCl added does the pH 10 643 Texas A M University Academic Success Center Spring 2019 CHEM 102 Dr Collins SI Leader Nikhil Manuel nsmanuel100 tamu edu https sites google com tamu edu sichemistry102 home Tuesday 6 30 7 30 ZACH 340 Wednesday 6 30 7 30 ZACH 353 Thursday 6 30 7 30 ZACH 340 Chapter 15 Solubility Conceptual Review a What is the general set up for a solubility question and the Ksp expression b What is the difference between solubility and molar solubility c How can the common ion effect affect solubility d What is a complex ion How is the Kf represented Notes a The ion that surrounds a complex ion is a ligand b Ligand increases solubility of a slightly soluble ionic compound if it forms a complex ion c pH can affect solubility observe slide 23 of Chapter 15 notes d In a basic compound lowering the pH can draw out the hydroxide making the compound more soluble Vice versa for an acidic solution Texas A M University Academic Success Center Spring 2019 CHEM 102 Dr Collins SI Leader Nikhil Manuel nsmanuel100 tamu edu https sites google com tamu edu sichemistry102 home Tuesday 6 30 7 30 ZACH 340 Wednesday 6 30 7 30 ZACH 353 Thursday 6 30 7 30 ZACH 340 Practice Problems a Lead II sulfate is a key component in lead acid car batteries Its solubility in water at 25 C is 4 25 10 3 g 100 mL solution What is the Ksp 19 5 b When lead II fluoride is shaken with pure water at 25 C the solubility is found to be 0 64 g L Calculate the Ksp c Calculate the solubility of Ca OH 2 in water if the Ksp is 6 5 10 6 d In relation to the previous question what is its solubility in 0 10 M Ca NO3 2 Texas A M University Academic Success Center 19 6 Spring 2019 CHEM 102 Dr Collins SI Leader Nikhil Manuel nsmanuel100 tamu edu https sites google com tamu edu sichemistry102 home Tuesday 6 30 7 30 ZACH 340 Wednesday 6 30 7 30 ZACH 353 Thursday 6 30 7 30 ZACH 340 e Which of the following will in increase in solubility with addition of acid 1 Lead II Bromide 4 Calcium Fluoride 2 Copper II Hydroxide 5 Zinc Sulfide 3 Iron II Sulfide 6 Silver Iodide 19 8 f Does a precipitate form when 0 100 L of 0 30 M Ca NO3 2 is mixed with 0 200 L of 0 060 M NaF Ksp of CaF2 is 3 2 10 11 19 9 g An industrial chemist converts Zn H2O 42 to the more stable Zn NH3 42 by mixing 0 50 L of 0 0020 M Zn H2O 42 and 25 0 L of 0 15 M NH3 What is the final concentration of Zn H2O 42 Kf of Zn NH3 42 is 7 8 108 19 10 Texas A M University Academic Success Center Spring 2019 CHEM 102 Dr Collins SI Leader Nikhil Manuel nsmanuel100 tamu edu https sites google com tamu edu sichemistry102 home Tuesday 6 30 7 30 ZACH 340 Wednesday 6 30 7 30 ZACH 353 Thursday 6 30 7 30 ZACH 340 Chapter 17 Electrochemistry Conceptual Review a When writing a redox reaction what is the order for balancing in acidic solutions What about basic solutions b What is the oxidation states rules that are common c EO cell is calculated how Notes a View Dr Collins notes for clarification b When in acidic solutions there should be H In basic solutions there should be OH This makes sense in regards to the environment c Anode is oxidized cathode is reduced d G nFEcell and Go nFEocell with n number of moles of electrons in reaction e F is Faradays constant f Eocell RT nF lnK 0 0592 V n logK Texas A M University Academic Success Center Spring 2019 CHEM 102 Dr Collins SI Leader Nikhil Manuel nsmanuel100 tamu edu https sites google com tamu edu sichemistry102 home Tuesday 6 30 7 30 ZACH 340 Wednesday 6 30 7 30 ZACH 353 Thursday 6 30 7 30 ZACH 340 Practice Problems a MnO4 S2O32 Mn2 SO42 balance in acidic conditions b NO3 S2 S8 NO2 balance in acidic conditions Texas A M University Academic Success Center Spring 2019 CHEM 102 Dr Collins SI Leader Nikhil Manuel nsmanuel100 tamu edu https sites google com tamu edu sichemistry102 home …