Electronegativity and acid strength

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305385703
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Electronegativity and acid strength

Postby 305385703 » Mon Dec 02, 2019 9:30 am

Why would an acid such as HClO be stronger than, say, HBrO?

Shail Avasthi 3C
Posts: 86
Joined: Fri Aug 30, 2019 12:17 am

Re: Electronegativity and acid strength

Postby Shail Avasthi 3C » Mon Dec 02, 2019 10:03 am

Oxoacids will be more acidic if the anion formed is stabilized by electronegative atoms which delocalize the negative charge. Chlorine is more electronegative than bromine, which means it will more effectively delocalize the negative charge on the oxygen, yielding a more stable anion – this causes its greater acidity.

sarahforman_Dis2I
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Re: Electronegativity and acid strength

Postby sarahforman_Dis2I » Mon Dec 02, 2019 10:12 am

305385703 wrote:Why would an acid such as HClO be stronger than, say, HBrO?


HClO would be a stronger acid because Cl is more electronegative than Br. Because of this, the Cl atom pulls electrons away from the hydrogen and towards the Cl. This means that it will be easier for the H+ ion to be released from the compound. Since it will be easier for the H+ ion to leave the atom, the acid will dissociate more and therefore, the acid will be stronger. I hope this helps.

Chantel_2I
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Re: Electronegativity and acid strength

Postby Chantel_2I » Mon Dec 02, 2019 11:15 pm

Electronegativity is one of the ways by which the resulting anion of an acid losing a proton could be stable. When the resulting anion is more stable, the reaction is more likely to occur because reactions favor stability. Since the reaction is more likely to occur, more of the acid will dissociate, releasing H+ ions, so it is a stronger acid.

britthanul234
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Joined: Wed Sep 18, 2019 12:21 am

Re: Electronegativity and acid strength

Postby britthanul234 » Mon Dec 02, 2019 11:21 pm

An acid losing a proton could be made stable through electronegativity. When the resulting anion is made stable, the following reactions will be stable as well. That means that more of the acid will dissociate, release H+ ions. Hence, it would be a stronger acid.

Minh Ngo 4G
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Joined: Thu Jul 25, 2019 12:17 am

Re: Electronegativity and acid strength

Postby Minh Ngo 4G » Mon Dec 02, 2019 11:24 pm

Since in both HBrO and HClO has the same OH bond, you have to look at the anion after the H+ has been removed. Then, the one with the element that is more electronegative is the stronger acid. Why? Because higher electronegativity means that element would pull on the electron from the partially negative charged O more and "spread it around the bond", making the whole thing more stable. So here, after the H+ is removed, you are left with ClO and BrO. Since Cl is more electronegative, HClO is the stronger acid.


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