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6D.11 part d

Posted: Fri Dec 06, 2019 4:19 pm
by Ellis Song 4I
Why is the pH of KBr neutral but the pH of KF in part c is basic?

Re: 6D.11 part d

Posted: Sat Dec 07, 2019 1:06 am
by Ryan 1K
In both parts, the K+ cation is a Group 1 element, so we know that it does not affect the pH. The difference is in the anion. The F- anion is the conjugate base of a weak acid (HF), so that means it will lower the pH by acting as a base. For HBr, the Br- anion is the conjugate base of a strong acid (HBr), so that means that the Br- will not affect the pH and will be a very weak base.