I was doing questions on organic chemistry. I came across tonnes of questions where I was required to compare basic and acidic strengths.
Comparing acidic strengths is fine — I remove an $\ce{H+}$ and compare the stability of the anion because my teacher told me a strong acid has a stable anion and explained the reason to me from an equilibrium point of view.
When it comes to comparing basic strengths what do we do?
Can I add an $\ce{H+}$ to the species and compare the resulting stability by resonance, hyperconjugation and inductive effect and then can conclude the more basic one will have a stabler cation?
Really baffled. Please do correct me if I am mistaken in my fundamentals.
Answer
Comparing acidic strengths is fine - I remove an H+ and compare the stability of the anion coz my teacher told me strong acid has a stable anion and explained me the reason from equilibrium point of view. When it comes to comparing basic strengths what do we do ?
You follow the same general idea - the stronger the base, the weaker its conjugate acid. Consider a generic base such as $\ce{B-}$ reacting with water, the acid in this case.
$\ce{B- + H2O <=> HB + HO-}$
The conjugate acid of $\ce{B-}$ is $\ce{HB}$. And the stronger that $\ce{HB}$ is as an acid, the more likely it is to protonate hyroxide ion and favor the left side of the equilibrium, thereby making the base weak.
Can I add an H+ to the species and compare the resulting stability by resonance ,hyperconjugation and inductive effect and then can I conclude the more basic one will have a stabler cation?
Yep, that's it.
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