Acid-Base Neutralization

[StarryNights]

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An EK 1001 problem on titration gave me 30 mL of 3 M acetic acid (pKa= 4.7) mixed with 50 mL of 3 M NaOH for me to determine the final pH. So I calculated pH taking into account acetic acid's pKa since I thought acetic acid is a weak acid so it wouldn't dissociate completely. In the EK solution though, they just found the moles of [H+] straight (30 mL x 3 M = 90 mmol) without taking into account its pKa. Can someone explain why the pKa doesn't matter in this case? Thanks!

 

[loveoforganic]

They didn't calculate moles of H+ in solution, they calculated moles of acid that would react with a strong base, which is all of them.