Question

what is the total ionic equation and the net ionic equation for the reaction between sodium benzoate and acetic acid? When I mixed the two chemicals in lab, there was no observable reaction. Why don't they react?

NaC6H5CO2 + CH3COOH = ??????

Answer 1

There is no observable reaction since:

NaC6H5CO2 --> Na+(aq) + C6H5CO2-(aq)

The sodium benzoate ionizes in solution to form aqueous ions...

Note that

C6H5CO2-(aq) is a conjugate base of the weak acid C6H5CO2H(aq)

C6H5CO2H(aq) <--> C6H5CO2-(aq) + H+(aq) Ka = 10^-4.20

the acetic aicd:

CH3COOH(aq) <--> CH3COO-(aq) + H+(aq) Ka = 10^-4.75

Since the acetic acid is a WEAKER acid than BENZOIC ACID

the benzoate ion is not likely to act as a base and accept H+ from solution

the weaker acid CH#COOH ( Acetic acid) will remain molecular

that is, won't donate H+ to solution, since it will act as a base, not as an acid

No reaciton will be seen since there is no rection possible