Determining Strength of an Acid/Base
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Determining Strength of an Acid/Base
How do you find whether a given acid or base is strong or weak? Does it relate to electronegativity?
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- Posts: 20
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Re: Determining Strength of an Acid/Base
When an acid is strong, the pH value is small, and the Ka is a big number. However when you have a strong base, the Kb value is a big number because (Ka)x(Kb)=Kw is an inverse relationship. so if Ka is a strong acid, then the value of Kb is big. Also strong bases have a higher pH value.
Also in the course reader there is a table of strong and weak acids and bases.
The bigger the difference in electronegativity of two elements in a molecule, the more acidic they are because their bonds are weaker. When the bonds are weaker, it is easier for water to remove a proton, which makes it a strong acid because strong acids must loose protons easily. More
Also in the course reader there is a table of strong and weak acids and bases.
The bigger the difference in electronegativity of two elements in a molecule, the more acidic they are because their bonds are weaker. When the bonds are weaker, it is easier for water to remove a proton, which makes it a strong acid because strong acids must loose protons easily. More
Last edited by Macy Matsukawa 3J on Wed Nov 25, 2015 1:08 am, edited 1 time in total.
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Re: Determining Strength of an Acid/Base
To determine the strength of an Acid/Base, you can calculate and interpret the Ka and Kb values.
Remember that Ka = [H+][A-] / [HA] and Kb = [BH+][OH-] / [B].
Ka and Kb are the acid and base dissociation constants respectively.
A higher Ka or Kb would mean a stronger acid or base respectively.
In general, strong acids and bases dissociate easily in water to form H+ ad OH-.
This suggests that they have a weaker bond between their H+ or OH- to the rest of the molecule than do weak acids and bases.
Remember that Ka = [H+][A-] / [HA] and Kb = [BH+][OH-] / [B].
Ka and Kb are the acid and base dissociation constants respectively.
A higher Ka or Kb would mean a stronger acid or base respectively.
In general, strong acids and bases dissociate easily in water to form H+ ad OH-.
This suggests that they have a weaker bond between their H+ or OH- to the rest of the molecule than do weak acids and bases.
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