I am currently struggling trying to understand buffer systems and more generally speaking, neutralising titrations of all varieties. Specifically, I came across this problem;
1.) Determine the pH of buffer solutions obtained by mixing 50,00 mL of 0,200M NaH2
a) 50,00 mL of 0,120M HCl (1,97)
b) 50,00 mL of 1,120M NaOH (7,37)
for a), my idea was to write the following equation:
which to my knowledge, can be regarded as a one-way?
Next, I wrote:
and HCl react at a molar ratio of 1:1, which is 0,006 mol (some sodium dihydrogenphosphate is left out), resulting in a 0,06M solution of H3
(total volume is now 100 mL)
Using the K1
, I figured out that in the second equation, [H3
] equals 0,017403, which in turn, results in the pH of 1,76. Did I go wrong somewhere or are the solutions wrong (written above)? Also, I'm guessing b) has pretty much the same idea? I got 6,68 for b) but I think this is wrong, since I have a strong feeling the system would have a basic pH.