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Part 1 Write the reversible reaction for Part 1 (include colors) Test tube __2____ Stress: _______________________________________________________________ How rxn tries to remove stress: _________________________________________________ Circle: Make more product or more reactant Circle: Favoring: Forward rxn or Backward rxn Circle: Shift Equilibrium to: Left(more reactant) or Right (more product) Solution turned: More Light Brown or More Red or No change Compare to lab observation: __________________________________________ Test tube ___3___ Stress: _______________________________________________________________ How rxn tries to remove stress: _________________________________________________ Circle: Make more product or more reactant Circle: Favoring: Forward rxn or Backward rxn Circle: Shift Equilibrium to: Left(more reactant) or Right (more product) Solution turned: More Light Brown or More Red or No change Compare to lab observation: __________________________________________ Test tube ___4___ Stress: _______________________________________________________________ How rxn tries to remove stress: _________________________________________________ Circle: Make more product or more reactant Circle: Favoring: Forward rxn or Backward rxn Circle: Shift Equilibrium to: Left(more reactant) or Right (more product) Solution turned: More Light Brown or More Red or No change Compare to lab observation: __________________________________________ Part 2 Write the reversible reaction for Part 2 (include colors) For this reaction you need to know a few more pieces of information. 1)HCl --> H+ (or H3O+) + Cl1- So, in a bucket of HCl solution, there is no HCl but only H+ and Cl1- ions. Therefore, adding HCl really means adding H+ (or H3O+) 2) NaOH ---> Na1+ + OH1- Then the OH1- + H+ ---> H2O |
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1. Write the two balanced reversible chemical reactions and the two additional chemical reaction (to help explain addition of HCl and NaOH). |
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Looking at the above two equation, one needs to realize that you can explain lab observations in two different ways with respect to LeChatlier's Principle. |
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2. For each different addition of chemical for Part I and Part II, explain using the four steps the color change stated in your observation table. |
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2a) OH1- from the NaOH consumes H+ as in the above reaction so adding the chemical is actually a decrease in [H+] or |
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2b)OH1- from the NaOH reacts with H+ to form H2O so adding the chemical is actually increase [H2O]. So, for the reactions with NaOH below, please alternate explanation (once using 2a & another times using 2b). Test tube ___5 (HCl added)___ Stress: _______________________________________________________________ How rxn tries to remove stress: _________________________________________________ Circle: Make more product or more reactant Circle: Favoring: Forward rxn or Backward rxn Circle: Shift Equilibrium to: Left(more reactant) or Right (more product) Solution turned: More Yellow or More Orange or No change Compare to lab observation: __________________________________________ Test tube _6 (HCl added)_____ Stress: _______________________________________________________________ How rxn tries to remove stress: _________________________________________________ Circle: Make more product or more reactant Circle: Favoring: Forward rxn or Backward rxn Circle: Shift Equilibrium to: Left(more reactant) or Right (more product) Solution turned: More Yellow or More Orange or No change Compare to lab observation: __________________________________________ Test tube ___6 (NaOH added)___ Stress: _______________________________________________________________ How rxn tries to remove stress: _________________________________________________ Circle: Make more product or more reactant Circle: Favoring: Forward rxn or Backward rxn Circle: Shift Equilibrium to: Left(more reactant) or Right (more product) Solution turned: More Yellow or More Orange or No change Compare to lab observation: __________________________________________ Test tube __7 (NaOH added)____ Stress: _______________________________________________________________ How rxn tries to remove stress: _________________________________________________ Circle: Make more product or more reactant Circle: Favoring: Forward rxn or Backward rxn Circle: Shift Equilibrium to: Left(more reactant) or Right (more product) Solution turned: More Yellow or More Orange or No change Compare to lab observation: __________________________________________ Test tube __8 (NaOH added)____ Stress: _______________________________________________________________ How rxn tries to remove stress: _________________________________________________ Circle: Make more product or more reactant Circle: Favoring: Forward rxn or Backward rxn Circle: Shift Equilibrium to: Left(more reactant) or Right (more product) Solution turned: More Yellow or More Orange or No change Compare to lab observation: __________________________________________ Test tube __8 (HCl added)_____ Stress: _______________________________________________________________ How rxn tries to remove stress: _________________________________________________ Circle: Make more product or more reactant Circle: Favoring: Forward rxn or Backward rxn Circle: Shift Equilibrium to: Left(more reactant) or Right (more product) Solution turned: More Yellow or More Orange or No change Compare to lab observation: __________________________________________ |
Looking at the above two equation, one needs to realize that you can explain lab observations in two different ways with respect to LeChatlier's Principle.
2a) OH1- from the NaOH consumes H+ as in the above reaction so adding the chemical is actually a decrease in [H+] or
2b)OH1- from the NaOH reacts with H+ to form H2O so adding the chemical is actually increase [H2O].
So, for the reactions with NaOH below, please alternate explanation (once using 2a & another times using 2b).