In: Chemistry
In Part B of the experiment you uses a weak base, sodium bicarbonate to completely convert a weak acid to a salt. Why was sodium bicarbonate able to completely convert the acid whereas many weak bases would have left some unreacted acid because of the equilibrium?
THe acid-base reaction are best performed when weak acid and strong base OR strong acid and weak base are reacted.
It is based on Bronsted-Lowry acid-base theory.
The fundamental concept of this theory is that when an acid and a base react with each other, the acid forms its conjugate base, and the base forms its conjugate acid by exchange of a proton.
acid + base -----> conjugate base + conjugate acid.
Now strong acid has more tendency to form conjugate base readily. While strong base easily forms conjugate acid compared to weak base.
So reaction between strong acid and weak base OR weak acid and strong base are more preferable compared to reaction between strong acid and strong base OR weak acid and weak base.
Here, Weak acid is reacted with weak base and sodium bicarbonate (Strong base)
So according to acid-base theory, Sodium bicarbonate will completely convert weak acid into its conjugate base compared to weak base.