Question

Why is NaHCO3 a base?

(I need someone to explain it using the ka values)

H2CO3 <--> HcO3- + H+ ka = 4.3x10^-7
HCO3- <--> CO3^2- + H+ ka = 5.61x10^-11

if I underestand correctly, the kb for the second equation is greater than the ka. Thus the reaction will not proceed forward, but rather produce more HCO3-. This is a basic tendency. Why is it more powerful than the first reaction?

thanks everyone!

Answer 1

NaHCO3 is a product of a strong base and a weak acid reaction. Thus it has weak basic properties.

HCO3- ion is actually amphoteric, which means it can act as a base or an acid. But it is weaker than a strong acid or a strong base.

HCO3- is amphoteric meaning it acts both as a B.L. Acid and a B.L. Base.. which is why it's used to neutralize both acid and base spills in the lab.