Identify the Bronsted-Lowry acid in the following reaction (consider the forward reaction only):?

Question

H2O + CO3-2 --> HCO3- + OH-

the possible answers are:

CO3-2

HCO3-

OH-

H2CO3

H2O

Answer 1

A Bronsted-Lowry  acid is defined as any substance that can donate a hydrogen ion (proton) and a Bronsted-Lowry base is any substance that can accept a hydrogen ion (proton). Thus, according to the BL definition, acids and bases must come in what is called conjugate pairs. I always use the mneumonic BAAD ( said bad).  base accepts, acid donates.  And whatever is conj. to that is either the base or acid in a weaker form. :)

Answer 2

That would be the H2O (H+)<- (OH-), strongly basic conditions favor the formation of the carbonate ion as a conjugate base to bicarbonate (HCO3), while in weakly basic conditions, the bicarbonate ion is is more likely to be the conjugate to carbonic acid (H2CO3).