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Why do solutions of weak acids have higher pH values than solutions of strong acids at the same concentration? Is it because a higher pH indicates a less acidic solution because the weak acid has not fully dissociated?
Like you said, weak acids do not dissociate 100%, so they will produce less H3O+, resulting in a higher pH value. The concentration of H3O+ will be lower than that of a stronger acid, since stronger acids almost always dissociates completely.
If you are saying higher pH in terms of numbers closer to 7 than yes you would be correct. If you think about a strong acid that has completely dissociated, the humber of H+ ions in that solution will be greater than that of a weak acid.
I also wanted to input that pH is also related to the concentration of Hydronium ions (H3O+). For example if you have a pH of 1 to convert that into concentration you would take the antilog of -1 (The reason you take the antilog is because pH=-log[H3O+] and we know that the ph is 1 so we solve for the concentration of H3O+.) When we convert it into concentration it would be 10^-1. So in respect to say pH 7. The hydronium concentration would be approximately 10^-7 for pH 7 and the concentration for pH 1 would be approximately 10^-1. When you compare both concentrations we can see that 10^-1 is larger than 10^-7. Hope this helps and clarified any confusion.
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