# are half of “H2SO4 pH sample problem” webpages just wrong, or am I wrong?

I did a Google search for "h2so4 pH sample problem" and went through the results, and it looks like about 50% of the webpages "explaining" how to do this problem give the wrong answer when calculating the pH of a solution of $\ce{H2SO4}$. The incorrect sources either (a) assume that each molecule of $\ce{H2SO4}$ donates only one proton (approximately true only at high concentrations); or (b) assume that each molecule of $\ce{H2SO4}$ donates both protons (approximately true only at low concentrations). Only about half of the sources do the problem correctly by assuming that all $\ce{H2SO4}$ molecules donate the first proton and then using the second dissociation constant to compute the degree of dissociation of the second proton.

I'm no expert, so am I missing something, or are half of the sources out there just wrong?

Googling "h2so4 pH sample problem", here are the first eight hits after removing pages that did not contain an $\ce{H2SO4}$ sample problem, and how I scored them:

So it looks like even for just a slightly-non-trivial problem, almost a majority of free online help resources get the answer wrong. Is there some subtlety I'm overlooking?

• And this is why I always told people to be careful about looking for help online. Personally, I've found that it's way worse that 50% for quantum mechanics problems... – chipbuster Jun 6 '18 at 8:03
• Yes, you got it right. The web is dark and full of errors. – Ivan Neretin Jun 6 '18 at 13:23
• @IvanNeretin I see what you've done here :D Nice pun. BTW I'm afraid OP already asked about it earlier. This question is kinda waste of time. Question is trivial, and no idea why someone would even dig through all these pseudo "resources". Also difference between 2.69 and 2.73 as far as pH goes is negligible and approximate calculations are employed often. Approximation isn't equal to error as every value describing physical world is approximate unless it's a constant made to be precise. – Mithoron Jun 6 '18 at 19:00
• I'm voting to close this question as off-topic because it's essentially a rant how people on internet are usually wrong, not a question. – Mithoron Jun 6 '18 at 20:11
• I had read your meta post yesterday and was planning to convert this into a proper Q&A, however, this isn't the way I would have done it. Your question: "am I missing something, or are half of the sources out there just wrong?" has the obvious answer that the sources are wrong. In fact, you've labeled them as being incorrect or correct yourself. I fail to see what is being asked, thus. – Gaurang Tandon Jun 7 '18 at 3:54