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1-1-2. What is the dissociation ratio of 1st dissociable proton of phosphoric acid at pH2.16, given the pKa is 2.16 or Ka is 6.92x10-3? Hint: Dissociation ratio = [A-]/([HA]+[A-]). What happen when pH=pKa? Ans: 50% or 0.5 ([A-]/[HA]=1).

1-2-3. What is the pH if you dissolve 0.5 M formic acid in water, given the pKa is 3.75 or Ka is 1.78x10-4? Hint: H+ comes from the formic acid molecule. [H+]+[HA]=1 Ans: pH=2.03

2-1-3. What is the pH if you add 30 ml of 0.3 M NaOH into 60 ml of 1 M formic acid? pKa of formic acid is 3.75. Hint: OH- comes from NaOH uses the HA molecule and convert it to AAns: pH=3.00 2-2-3. How do you make 0.2 liter of pH 4, 0.5 M acetic acid buffer (pKa=4.76) with HOAc (molecular weight 60.05) and NaOAc (molecular weight 82.03)? Hint: pH = pKa + log [A–]/[HA] ; molecular weight = g/mole, M=mole/liter Ans: Weight 5.12 g HOAc and 1.21 g NaOAc, add water to make total volume of 0.2 L.

3-3 What is the direction of this reaction at CO=0.2 atm, H2=0.5 atm, CH3OH=1.4 atm, K=14.5? CO(g)+2H2(g)→CH3OH(g) Ans: Q=28, the reaction shifts left, favors the reactants...